Cycloolefin addition copolymer and optical transparent material

ABSTRACT

A cyclic olefin addition copolymer obtained by copolymerizing a cyclic olefin compound having a side chain substituent group with a ring structure, such as endo-tricyclo[4.3.0.1 2,5 ]deca-3,7-diene or endo-tricyclo-[4.3.0.1 2,5 ]deca-3-ene, with another cyclic olefin compound such as bicyclo[2.2.1]hept-2-ene, and further with a cyclic olefin compound having a hydrolysable silyl group as needed, or hydrogenating after copolymerization; a composition for crosslinking in which a specific crosslinking agent is incorporated; a crosslinked product obtained by crosslinking the composition; an optical material containing the copolymer, the composition or the crosslinked product; and a method for producing the copolymer in which addition polymerization is conducted using a specific nickel catalyst.

TECHNICAL FIELD

The present invention relates to a cyclic olefin addition copolymerexcellent in optical transparency, heat resistance and toughness, andsuitable for optical material applications; a composition thereof; andan optical material using the same.

BACKGROUND ART

In recent years, with demands for weight saving, miniaturization and anincrease in density, substitution by optical transparent resins hasprogressed in the, fields of optical parts such as lenses, and liquidcrystal display element parts such as backlights, light guiding platesand substrates, for which inorganic glass has hitherto been used.However, further improvements have been required for the opticaltransparent resin materials in characteristics such as heat resistance,low moisture absorption, adhesioness and stickiness and breakingstrength, as well as optical transparency.

Many addition polymers of cyclic olefin compounds represented bybicyclo[2.2.1]hept-2-ene(norbornene) have hitherto been proposed asmaterials excellent in transparency and heat resistance (Japanese PatentLaid-Open Publication (Hei) 4-63807, Japanese Patent Laid-OpenPublication (Hei) 8-198919, Published Japanese Translation (Hei)9-508649 of PCT International Patent Application and Published JapaneseTranslation (Hei) 11-505880) of PCT International Patent Application.

However, the conventional norbornene addition polymers have adisadvantage similar to that of glass such as low toughness to causefragility, when formed into a film, a sheet or the like, and aredifficult to be handled.

Further, a polymer difficult to perform injection molding or extrusionmolding because of it high glass transition temperature is formed into afilm or a sheet by a solution cast method in many cases. In that case,although there is generally employed a method of dissolving the polymerin a solvent, applying or flow casting the solution onto a support, andevaporating the solvent in the polymer with gradual heating, the polymeris required to be homogeneously dissolvable in the solvent in thevicinity of room temperature in terms of that process. However, thenorbornene addition polymer obtained by using a catalyst of zirconium,chromium, palladium or the like has no solubility in a hydrocarbonsolvent or the like at room temperature, so that it is difficult to formthe polymer into a film, a sheet, a thin membrane or the like by thesolution cast method.

It is also possible to solubilize the copolymer in a hydrocarbon solventsuch as cyclohexane, toluene or a mixture thereof at room temperature byformation of a copolymer in which a long chain alkyl group or atrialkoxysilyl group is introduced into a side chain of a cyclic olefin,and to improve toughness at the same time. However, on the other hand,the glass transition temperature decreases and the coefficient of linearexpansion increases with an increase in the content thereof, resultingin the polymer having inferior heat resistance and dimensional stability(J. Polymer Sci. Part B, Vol. 37, 3003 (1999)).

Further, although many copolymers of a cyclic olefin compound and anon-cyclic olefin compound such as ethylene have been known, the glasstransition temperature thereof decreases, and they are accompanied by andecrease in heat resistance (Japanese Patent Laid-Open Publication (Sho)61-292601, U.S. Pat. No. 2,883,372 and Makromol. Chem. Macromol. Symp.,Vol. 47, 83 (1991)). Furthermore, as a means effective for theproduction of these copolymers, there has been known a catalyst systemcontaining zirconium, titanium or vanadium, such as a metallocene.However, this catalyst scarcely exhibits polymerization ability formonomers containing a polar group, so that it is difficult to impartfunctions such as introduction of a crosslinking group such as ahydrolytic silyl group, and adhesioness.

On the other hand,tricyclo[4.3.0.1^(2.5)]deca-3,7-diene(dicyclopentadiene) addition(co)polymers having a cyclic side chain structure as a cyclic olefin,hydrogenated products thereof ortricyclo[4.3.0.1^(2.5)]deca-3-ene(dihydro-dicyclopentadiene) addition(co)polymers are known in Polymer Letter, Vol. 8, 573 (1970), Polymer,Vol. 10, 393 (1969), Japanese Patent Laid-Open Publication (Sho)59-164316, U.S. Pat. No. 2,883,372, Published Japanese Translation2000-509754 of PCT International Patent Application, Japanese PatentLaid-Open Publication (Hei) 3-45612, Japanese Patent Laid-OpenPublication (Hei) 4-268312, Japanese Patent Laid-Open Publication (Sho)61-292601, Japanese Patent Laid-Open Publication (Hei) 4-63807, JapanesePatent Laid-Open Publication (Hei) 5-239148, Japanese Patent Laid-OpenPublication (Hei) 6-202091, Japanese Patent Laid-Open Publication2001-19723, Japanese Patent Laid-Open Publication 2001-98035,Organometallics, Vol. 20, 2802-2812 (2001), Polymer Science Ser. A, Vol.38, 255-260 (1996), Macromol. Symp., Vol. 89, 433-442 (1995) and thelike.

Polymer Letter, Vol. 8, 573 (1970) describes polymers having a numberaverage molecular weight of 3, 500 or less, such as dicyclopentadieneand dihydrodicyclopentadiene obtained by using a cationic polymerizablecatalyst. Polymer, Vol. 10, 393 (1969) describes that addition polymershaving number average molecular weights of 1,950 and 860 are obtained bypolymerizing dicyclopentadiene using a palladium catalyst.

Japanese Patent Laid-Open Publication (Sho) 59-164316 describes acopolymer obtained by using dihydrodicyclopentadiene and anorbornene-containing monomer. However, this is a petroleum hydrocarbonresin for adhesion and adhesive agents, which is obtained by use of acationic polymerizable catalyst and has a molecular weight of 3,000 orless.

U.S. Pat. No. 2,883,372 describes an addition copolymer of ethylene anddihydrodicyclopentadiene. However, this is limited to a melt formablecopolymer. Moreover, a monomer component is also limited, so that it isunable to impart a function such as crosslinking by introduction of asubstituent group or the like.

Published Japanese Translation 2000-509754 of PCT International PatentApplication describes a hydrogenated product of a copolymer of anα-olefin and dicyclopentadiene using a metallocene catalyst using oneselected from titanium, zirconium and hafnium. However, the content ofthe α-olefin exceeds 50 mol % in this system, so that the hydrogenatedcopolymer thereof with ethylene has a glass transition temperature oflower than 200° C.

Further, in Japanese Patent Laid-Open Publication (Sho) 61-292601,Japanese Patent Laid-Open Publication (Hei) 3-45612, Japanese PatentLaid-Open Publication (Hei) 6-202091 and Japanese Patent Laid-OpenPublication (Hei) 4-268312, addition (co)polymers using polycyclicmonomers such as various norbornenes or tetracyclododecenes as monomersare claimed, and tricycloolefin compounds such as dicyclopentadiene anddihydrodicyclopentadiene are also contained therein. However, no exampleof actual polymerization using dihydrodicyclopentadiene is described,and properties thereof are not clarified. Further, all exemplified arecopolymers with α-olefins such as ethylene, and the glass transitiontemperatures thereof are lower than 200° C. Furthermore, the polymersare obtained by using a catalyst system comprising a compound of atransition metal such as vanadium, zirconium, titanium, hafnium,vanadium, niobium or tantalum and an alkylalumoxane. However, these onlyexhibit extremely low polymerization ability to a polar group-containingmonomer, so that it is difficult to impart a function by introduction ofa polar group.

Japanese Patent Laid-Open Publication (Hei) 4-63807 discloses aproduction method using a norbornene polymer and a catalyst containing anickel compound and an alkylalumoxane as main components, and norbornenehomopolymers are mainly described in examples.

However, there is no example of using an addition (co)polymer containingrepeating units derived from a tricycloolefin compound as particularlyspecified in the present invention, and the possibility that thisaddition (co)polymer shows specific physical properties is not describedat all.

Japanese Patent Laid-Open Publication (Hei) 5-239148 describes addition(co)polymers using tricyclic norbornene monomers such asdicyclopentadiene and dihydrodicyclopentadiene as monomers, andhydrogenated products thereof. However, they are polymers polymerized byusing a palladium complex catalyst.

Japanese Patent Laid-Open Publication 2001-19723 exemplifies an additioncopolymer of a norbornene and cyclopentadiene using a catalystcontaining a compound of a transition metal such as nickel or palladium.Further, Japanese Patent Laid-Open Publication 2001-98035 describes anaddition copolymer of a norbornene and a monomer having an unsaturatedbond outside a norbornene ring, such as dicyclopentadiene, using apalladium complex and a Lewis acid as a catalyst. However, bothexemplify no hydrogenated product thereof, and are silent on thesolubility in a hydrocarbon solvent.

Polymer Science Ser. A, Vol. 38, 255-260 (1996) describes that whenexo-dicyclopentadiene is used, an addition polymer of cyclopentadieneusing a nickel compound and a halogenated organic aluminum as a catalystprovides a high-molecular weight polymer, but whenendo-dicyclopentadiene is used, it provides only a low-molecular weightpolymer. However, no hydrogenated product is described also therein.

Organometallics, Vol. 20, 2802-2812 (2001) discloses a homopolymer ofdicyclopentadiene using a palladium catalyst.

Macromol. Symp., Vol. 89, 433-442 (1995) describes an addition polymerof exo-dihydrodicyclopentadiene using a palladium catalyst. Thisaddition polymer is subjected to gel permeation chromatography (GPC)measurement in a chlorobenzene solvent, and the solubility inchlorobenzene is described. However, there is no description for thesolubility in a hydrocarbon solvent such as toluene or cyclohexane.

A homopolymer of endo-dicyclopentadiene using a catalyst containing apalladium compound, a nickel compound, a chromium compound or the likeis insoluble in a general hydrocarbon solvent at room temperature inalmost all cases. Also for norbornene, a homopolymer obtained by using acatalyst of zirconium, chromium, palladium or the like is insoluble inmany solvents at room temperature. This means that the polymers obtainedby these methods are difficult to be not only melt formed, but alsoformed by the solution cast method.

In Published Japanese Translation (Hei) 9-508649 of PCT InternationalPatent Application, it is presumed that the reason for the largedifference in the solubility of a cyclic olefin addition polymerdepending on the catalyst, particularly the transition metal speciesthereof, is caused by the difference in a microstructure when a cyclicolefin is addition polymerized. That is to say, it is described thatalthough the addition polymerization of the cyclic olefin can form, forexample, repeating units which are addition polymerized at the2,7-positions, as well as ordinary repeating units which are additionpolymerized at the 2,3-positions, a nickel catalyst provides relativelymany repeating units formed by addition polymerization at the2,7-positions compared to a palladium catalyst, resulting in animprovement in the solubility of the polymer in the hydrocarbon solvent.

Further, the addition (co)polymer obtained from dicyclopentadiene hasunsaturated bonds in side chains, so that crosslinking reaction ordiscoloration to yellow occurs under high temperatures to cause poorheat deterioration resistance. Accordingly, the cyclic olefin polymerhaving unsaturated bonds in side chains is unfavorable.

Thus, there has never been known a cyclic olefin (co)polymer whichdissolves in a hydrocarbon solvent at room temperature and can be formedinto a film or a sheet by the solution cast method, and the film orsheet of which has toughness and are not impaired in the coefficient oflinear expansion.

On the other hand, as related art making reference to a stereoisomer ofa cyclic olefin, Japanese Patent Laid-Open Publication (Hei) 3-163114(Japanese Patent No. 2,795,486) discloses a copolymer obtained fromethylene and a tetracyclododecene, and Japanese Patent No. 3,203,029discloses a random cyclic olefin copolymer obtained from ethylene and anaromatic series-containing norbornene. Both copolymers are characterizedin that the use of one having high exo-form content in a stericconfiguration of a substituent group of a norbornene structure improvesheat resistance and mechanical strength.

As a result of intensive studies in view of the above-mentionedproblems, the present inventors have discovered that a cyclic olefinaddition copolymer obtained by addition polymerization of a monomercontaining a specific tricycloolefin compound in which the ratio of theendo-form in stereoisomers is 80% or more, using a specific nickelcatalyst, and further hydrogenation as needed, is soluble in any one oftoluene, cyclohexane and a mixed solvent thereof at 25° C., alsoexcellent in heat resistance and mechanical strength, and possible tointroduce a crosslinkable group, and that the resulting crosslinkedproduct is excellent in optical transparency and heat resistance,excellent in toughness and low in the coefficient of linear expansion,so that it is a material suitable for a sheet, a film and a thinmembrane for optical material applications, thus leading to thecompletion of the present invention.

DISCLOSURE OF THE INVENTION

The present invention provides a cyclic olefin addition copolymercontaining a specific structure described below, a crosslinkablecomposition, a crosslinked product thereof, an application of thecopolymer (composition) and a method for producing the copolymer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a ¹H-NMR spectrum of a copolymer obtained in Example 1;

FIG. 2 is a ¹H-NMR spectrum of a copolymer obtained in Example 2;

FIG. 3 is a ¹H-NMR spectrum of a copolymer obtained in Example 3;

FIG. 4 is a ¹H-NMR spectrum of a copolymer obtained in Example 4;

FIG. 5 is a ¹H-NMR spectrum of a copolymer obtained in Example 5;

FIG. 6 is a ¹H-NMR spectrum of a copolymer obtained in Example 6;

FIG. 7 is a ¹H-NMR spectrum of a copolymer obtained in Example 7;

FIG. 8 is a ¹H-NMR spectrum of a copolymer obtained in Example 8;

FIG. 9 is a ¹H-NMR spectrum of a copolymer obtained in Example 9;

FIG. 10 is a ¹H-NMR spectrum of a copolymer obtained in Example 10;

FIG. 11 is a ¹H-NMR spectrum of a copolymer obtained in Example 11; and

FIG. 12 is a ¹H-NMR spectrum of a copolymer obtained in Example 12;

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is described in detail below.

The cyclic olefin addition copolymer of the present invention is acyclic olefin addition copolymer containing at, least one repeating unit(a) selected from the following formulas (1-1) to (1-4) and a repeatingunit (b) represented by the following general formula (2), and isobtained by addition polymerization of a tricycloolefin compound whichforms the repeating unit (a) after addition polymerization, and in whichthe ratio of the endo-form (stereoisomer) is 80% or more, or furtherhydrogenating the resulting copolymer when an olefinic unsaturated bondexists therein:

In formulas (1-1) to (1-4), R¹ to R²⁰ each independently represent asubstituent group selected from a hydrogen atom, a halogen atom and ahydrocarbon or halogenated hydrocarbon group having 1 to 20 carbonatoms;

In formula (2), A¹ to A⁴ each independently represent a hydrogen atom, ahalogen atom or a hydrocarbon or halogenated hydrocarbon group having 1to 20 carbon atoms, and m is 0 or 1.

The repeating unit (a) contained in the cyclic olefin addition copolymerof the present invention is formed by addition polymerization of amonomer (hereinafter correctively referred to as “specific monomer(a-1)”) selected from tricycloolefin compounds represented by thefollowing general formulas (7-1) to (7-4):

In formulas (7-1) to (7-4), R¹to R²⁰ are the same as defined forformulas (1-1) to (1-4).

Further, the repeating unit (a) contained in the cyclic olefin additioncopolymer of the present invention is also formed by additionpolymerization of a monomer (hereinafter correctively referred to as“specific monomer (a-2)”) selected from tricycloolefin compoundsrepresented by the following general formulas (8-1) to (8-7), and then,hydrogenating the resulting polymer:

In formulas (8-1) to (8-7), R¹ to R¹⁸ are the same as defined forformulas (1-1) to (1-4).

Specific examples of the above-mentioned specific monomers (a-1) includethe following, but the present invention is not limited thereto.

-   -   Tricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   1-methyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   1-methoxytricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   2-methyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   5-methyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   6-methyltricyclo[4.3 0.1^(2,5)]deca-3-ene,    -   6-ethyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   9-methyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   9-ethyltricyclo [4.3.0.1^(2,5)]deca-3-ene,    -   10-methyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   10-ethyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   10-phenyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   10-cyclohexyltricyclo[4.3.0.1^(2,5)]deca-3-ene,    -   tricyclo [4.2.0.1^(2,5)]nona-3-ene,    -   2-methyltricyclo[4.2.0.1^(2,5)]nona-3-ene,    -   7-methyltricyclo[4.2.0.1^(2,5)]nona-3-ene,    -   tricyclo[4.4.0.1^(2,5))undeca-3-ene,    -   1-methyltricyclo[4.4.0.1^(2,5)]undeca-3-ene,    -   2-methyltricyclo[[4.4.0.1^(2,5)]undeca-3-ene,    -   2-ethyltricyclo[4.4.0.1^(2,5)]undeca-3-ene,    -   8-methyltricyclo[4.4.0.1²⁵]undeca-3-ene,    -   tricyclo[6.4.0.1^(2,5)]undeca-3-ene,    -   2-methyltricyclo[6.4.0.1^(2,5)]trideca-3-ene, and    -   8-methyltricyclo[6.4.0.1^(2,5)]trideca-3-ene.

Of these, tricyclo[4.3.0.1^(2,5)]deca-3-ene is preferably used in termsof ready availability as a raw material and a balance between the heatresistance and mechanical characteristics of the resulting copolymer.

They may be used either alone or in combination of two or more of them.

Specific examples of the above-mentioned specific monomers (a-2) includethe following, but the present invention is not limited thereto.

-   -   Tricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   1-methyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   2-methyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   2-ethyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   5-methyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   6-methyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   6-ethyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   10-methyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   10-ethyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   10-phenyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   10-cyclohexyltricyclo[4.3.0.1^(2.5)]deca-3,7-diene,    -   tricyclo[4.4.0.1^(2.5)]undeca-3,7-diene,    -   1-methyltricyclo[4.4.0.1^(2.5)]undeca-3,7-diene,    -   2-methyltricyclo[4.4.0.1^(2.5)]undeca-3,7-diene,    -   2-ethyltricyclo[4.4.0.1^(2.5)]undeca-3,7-diene,    -   7-chlorotricyclo[4.4.0.1^(2.5)]undeca-3,7-diene,    -   7-fluorotricyclo[4.4.0.1^(2.5)]undeca-3,7-diene,    -   8-methyltricyclo[4.4.0.1^(2.5)]undeca-3,7-diene,    -   tricyclo[4.4.0.1^(2.5) ]undeca-3,8-diene,    -   1-methyltricyclo[4.4.0.1^(2.5)]undeca-3,8-diene,    -   2-methyltricyclo[4.4.0.1^(2.5)]undeca-3,8-diene,    -   2-ethyltricyclo[4.4.0.1^(2.5)]undeca-3,8-diene,    -   8-methyltricyclo[4.4.0.1^(2.5)]undeca-3,8-diene,    -   tricyclo[6.4.0.1^(2.5)]trideca-3,11-diene,    -   2-methyltricyclo[6.4.0.1^(2.5)]trideca-3,11-diene,    -   8-methyltricyclo[6.4.0.1^(2.5)]trideca-3,11-diene,    -   tricyclo[6.4.0.1^(2.5)]trideca-3,10-diene,    -   2-methyltricyclo[6.4.0.1^(2.5)]trideca-3,10-diene,    -   8-methyltricyclo[6.4.0.1^(2.5)]trideca-3,10-diene,    -   tricyclo[6.4.0.1^(2.5)]trideca-3,9-diene,    -   2-methyltricyclo[6.4.0.1^(2.5)]trideca-3,9-diene, and    -   9-methyltricyclo[6.4.0.1^(2.5)]trideca-3,9-diene.

Of these, tricyclo[4.3.0.1^(2.5)]deca-3,7-diene is preferably used interms of ready availability as a raw material and a balance between theheat resistance and mechanical characteristics of the resultingcopolymer.

They may be used either alone or in combination of two or more of them.

When the addition copolymer of the present invention is obtained byusing specific monomer (a-2), the addition copolymer is necessary to behydrogenated after addition polymerization. The presence of an olefinicunsaturated bond in the copolymer is undesirable because the copolymersuffers oxidation by oxygen under high temperatures or deterioration byheat. In the addition copolymer, it is therefore required that 90 mol %or more, preferably 95 mol % or more, more preferably 99 mol % or moreof the unsaturated bonds are hydrogenated.

Although the above-mentioned specific monomers (a-1) and (a-2) areavailable in the present invention, it is preferred to use theabove-mentioned specific monomer (a-1) in that hydrogenation reaction isnot indispensable. It is most preferred to usetricyclo[4.3.0.1^(2.5)]deca-3-ene among others.

In the above-mentioned specific monomers (a-1) and (a-2), the endo-formand the exo-form exist as stereoisomers. In the above-mentioned relatedart, it is described that the use of a tetracyclododecene and anaromatic series-containing norbornene having high exo-form contentimproves mechanical strength in the copolymer of ethylene and a cyclicolefin. However, in the present invention, surprisingly, it has beenrevealed that the monomer having higher endo-form content givesexcellent characteristics of the resulting copolymer such as strength,particularly breaking strength and breaking elongation measured by atensile test, and excellent toughness, quite contrary to the relatedart. That is to say, in the production of the copolymer of the presentinvention, it is necessary that the ratio of the endo-form in specificmonomers (a-1) and/or (a-2) used is at least 80 mol % or more, andpreferably 90 mol % or more. When this ratio is less than 80 mol %, nosatisfactory performance is obtained in characteristics of the resultingcopolymer such as breaking strength and breaking elongation, andtoughness is deteriorated, resulting in fragility of a formed articlesuch as a film or a sheet.

The repeating unit (b) contained in the cyclic olefin addition copolymerof the present invention is formed by addition polymerization of amonomer (hereinafter referred to as “specific monomer (b)”) selectedfrom cyclic olefin compounds represented by the following generalformula (9):

In formula (9), A¹ to A⁴, X and m are the same as defined for generalformula (2).

As such specific monomers (b), for example, the following compounds areused either alone or in combination of two or more of them, but thepresent invention is not limited to these specific examples.

-   -   Bicyclo[2.2.1]hept-2-ene,    -   5-methylbicyclo[2.2.1]hept-2-ene,    -   5-ethylbicyclo[2.2.1]hept-2-ene,    -   5-propylbicyclo[2.2.1]hept-2-ene,    -   5-butylbicyclo[2.2.1]hept-2-ene,    -   5-hexylbicyclo[2.2.1]hept-2-ene,    -   5-decylbicyclo[2.2.1]hept-2-ene,    -   5-methyl-5-ethyl-bicyclo[2.2.1]hept-2-ene,    -   5-fluorobicyclo[2.2.1]hept-2-ene,    -   5-chlorobicyclo[2.2.1]hept-2-ene,    -   b 5,6-dimethylbicyclo[2.2.1]hept-2-ene,    -   5-phenylbicyclo[2.2.1]hept-2-ene,    -   5-cyclohexylbicyclo[2.2.1]hept-2-ene,    -   5-cyclooctylbicyclo[2.2.1]hept-2-ene,    -   5-indanylbicyclo [2.2.1]hept-2-ene,    -   tetracyclo[4.4.0.1^(2.5).1^(7,10)]dodeca-3-ene,    -   8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodeca-3-ene, and    -   8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodeca-3-ene.

Of these, bicyclo[2.2.1]hept-2-ene is preferred in that polymerizationactivity of addition polymerization is high, and in that the coefficientof linear expansion of the resulting cyclic olefin addition copolymerand a crosslinked product thereof decreases.

In the cyclic olefin addition copolymer of the present invention, thephysical characteristics of the resulting copolymer, the solubilitythereof in an organic solvent, and the like can be controlled byselecting the kind of repeating unit (b) and the ratio thereofcontained. For example, the solubility in an organic solvent and theglass transition temperature can be controlled by optionally containingrepeating units derived from an alkyl group-containing cyclic olefinsuch as 5-hexylbicyclo[2.2.1]hept-2-ene, and flexibility can be impartedto a formed article such as a film or a sheet. However, when the ratiothereof is too high, the problems of a decrease in heat resistance ormechanical strength and deterioration in the coefficient of linearexpansion are encountered in some cases. The total of the ratio of therepeating units (b) is from 10 to 90 mol %, preferably from 20 to 90 mol%, and more preferably from 30 to 70 mol %, in the whole repeatingunits. When the ratio thereof exceeds 90 mol %, breaking elongationdecreases and toughness is deteriorated, resulting in brittleness andfragility of a formed article such as a film or a sheet. On the otherhand, when it is less than 10 mol %, a problem of decrease arises withrespect to the solubility in toluene, cyclohexane or a mixed solventthereof at 25° C. in some cases.

Addition polymerization using specific monomer (b) mainly forms therepeating units (b). In that case, a repeating unit (d) represented bythe following general formula (6) is also formed. For example, when m is0 in general formula (9), the repeating unit (b) indicates a repeatingunit polymerized by 2,3-addition, and the repeating unit (d) indicates arepeating unit polymerized by 2,7-addition. Further, when m is 1 ingeneral formula (9), the repeating unit (b) indicates a repeating unitpolymerized by 3,4-addition, and the repeating unit (d) indicates arepeating unit polymerized by 3,11-addition.

In formula (6), A¹ to A⁴ and m are the same as defined for generalformula (2).

Although it is difficult to determine the quantity of the repeatingunits (d) in the cyclic olefin addition copolymer of the presentinvention, the presence of the repeating units (d) formed by2,7-addition or 3,11-addition can be confirmed by strong absorptionobserved in the region of CH absorption which appears at 45 to 55 ppm ofa ¹³C-NMR spectrum (nuclear magnetic resonance spectrum).

Further, the cyclic olefin addition copolymer of the present inventioncan contain a repeating unit (c) represented by the following generalformula (3), as well as the repeating unit (a) and the repeating unit(b):

In formula (3), B¹ to B⁴ each independently represent a hydrogen atom, ahalogen atom, a hydrocarbon or halogenated hydrocarbon group having 1 to20 carbon atoms, a hydrolysable silyl group or a polar group representedby —(CH₂)_(k)X, and at least one of B¹ to B⁴ is a hydrolysable silylgroup or a substituent group selected from polar groups represented by—(CH₂)_(k)X, wherein X is —C(O)OR²¹ or —OC(O)R²², R²¹ and R²² are asubstituent group selected from hydrocarbon or halogenated hydrocarbongroups having 1 to 20 carbon atoms, and k is an integer of 0 to 3.Further, B¹ to B⁴ may be a ring structure such as a hydrocarbon orheterocyclic ring formed from B¹ and B³ or B² and B⁴, or an alkylidenylgroup formed from B¹ and B² or B³ and B⁴. p represents an integer of 0to 2.

The repeating unit (c) is formed by addition polymerization of a monomer(hereinafter referred to as “specific monomer (c)”) selected from cyclicolefin compounds represented by the following general formula (10):

In formula (10), B¹ to B⁴ and p are the same as defined for generalformula (3).

As such specific monomers (c), for example, the following compounds areused either alone or in combination of two or more of them, but thepresent invention is not limited to these specific examples.

Examples of specific monomers (c) having a polar group represented by—(CH₂)_(k)X include

-   -   methyl bicyclo[2.2.1]hept-5-ene-2-carboxylate,    -   ethyl bicyclo[2.2.1]hept-5-ene-2-carboxylate,    -   butyl bicyclo[2.2.1]hept-5-ene-2-carboxylate,    -   methyl 2-methylbicyclo[2.2.1]hept-5-ene-2carboxylate,    -   ethyl 2-methylbicyclo[2.2.1]hept-5-ene-2-carboxylate,    -   propyl 2-methylbicyclo[2.2.1]hept-5-ene-2carboxylate,    -   butyl 2-methylbicyclo[2.2.1]hept-5-ene-2-carboxylate,    -   trifluoroethyl 2-methylbicyclo[2.2.1]hept-5-ene-2-carboxylate,    -   ethyl 2-methylbicyclo[2.2.1]hept-5-ene-2-acetate,    -   2-methylbicyclo[2.2.1]hept-5-enyl acrylate,    -   2-methylbicyclo[2.2.1]hept-5-enyl methacrylate,    -   dimethyl bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate,    -   diethyl bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate,    -   8-methyl-8-carboxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-dodeca-3-ene,        and    -   8-methyl-8-carboxyethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-dodeca-3-ene.

Further, as the hydrolysable silyl group, one represented by generalformula (4) or general formula (5) is desirably used.

In formula (4) and formula (5), R²³, R²⁴ and R²⁵ each independentlyrepresent a hydrogen atom or a substituent group selected from an alkylgroup having 1 to 20 carbon atoms, a cycloalkyl group and an aryl group,R²⁶, R²⁷ and R²⁸ each independently are a hydrogen atom or a substituentgroup selected from an alkyl group having 1 to 20 carbon atoms, acycloalkyl group, an aryl group, an alkoxyl group, an allyloxy group anda halogen atom, at least one of R²⁶, R²⁷ and R²⁸ is a substituent groupselected from an alkoxyl group, an allyloxy group and a halogen atom,and n represents an integer of 0 to 5. Further, Y represents ahydrocarbon residue of an aliphatic diol having 2 to 20 carbon atoms, analicyclic diol or an aromatic diol.

Examples of specific monomers (c) having the hydrolysable silyl grouprepresented by general formula (4) include

-   -   5-[1′-methyl-2′,5′-dioxa-1′-silacyclopentyl]bicyclo-[2.2.1]hept-2-ene,    -   5-[1′-methyl-3′,3′,4′,4′-tetraphenyl-2′,5′-dioxa-1′-silacyclopentyl]bicyclo[2.2.1]hept-2-ene,    -   5-[1′,3′,3′,4′,4′-pentamethyl-2′,5′-dioxa-1′-silacyclopentyl]bicyclo[2.2.1]hept-2-ene,    -   5-[1′-phenyl-2′,5′-dioxa-1′silacyclopentyl]bicyclo-[2.2.1]hept-2-ene,    -   5-[1′-ethyl-2′,5′-dioxa-1′silacyclopentyl]bicyclo-[2.2.1]hept-2-ene,    -   5-[1′,3′-dimethyl-2′,5′-dioxa-1′silacyclopentyl]-bicyclo[2.2.1]hept-2-ene,    -   5-[1′,3′,4′-trimethyl-2′,5′-dioxa-1′-silacyclopentyl]bicyclo[2.2.1]hept-2-ene,    -   5-[1′-methyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo-[2.2.1]hept-2-ene,    -   5-[1′-ethyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo-[2.2.1]hept-2-ene,    -   5-[1′,3′-dimethyl-2′,6′-dioxa-1′-silacyclohexyl]-bicyclo[2.2.1]hept-2-ene,    -   5-[1′,4′,4′-trimethyl-2′,6′-dioxa-1′-silacyclohexyl]-bicyclo[2.2.1]hept-2-ene,    -   5-[1′,4′,4′-trimethyl-2′,6′-dioxa-1′-silacyclohexyl]-methylbicyclo[2.2.1]hept-2-ene,    -   5-[1′,4′,4′-trimethyl-2′,6′-dioxa-1′-silacyclohexyl]-ethylbicyclo[2.2.1]hept-2-ene,    -   5-[1′-phenyl-4′,4′-dimethyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo[2.2.1]hept-2-ene,    -   5-[1′-methyl-4′-phenyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo[2.2.1]hept-2-ene,    -   5-[3′-methyl-2′,4′-dioxa-3′-silaspiro[5.5]undecyl]-bicyclo[2.2.1]hept-2-ene,    -   5-[1′-methyl-4-ethyl-4′-butyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo[2.2.1]hept-2-ene,    -   5-[1′-methyl-3′,3′-dimethyl-5′-methylene-2′,6′-dioxa-1′-silacyclohexyl]bicyclo[2.2.1]hept-2-ene,    -   5-[1′-phenyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo-[2.2.1]hept-2-ene,    -   5-[1′-methyl-3′-phenyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo[2.2.1]hept-2-ene,    -   5-[1′,4′,4′-trimethyl-2′,6′-dioxa-1′-silacyclohexyl]-7-oxabicyclo[2.2.1]hept-2-ene,    -   5-[1′-methyl-2′,6′-dioxa-1′-silacyclohexyl]-7-oxa-bicyclo[2.2.1]hept-2-ene,    -   5-[1′-methyl-2′,7′-dioxa-1′-silacycloheptyl]bicyclo-[2.2.1]hept-2-ene,    -   8-[1′,4′,4′-trimethyl-2′,6′-dioxa-1′-silacyclohexyl]-tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodeca-3-ene,    -   8-[1′-methyl-2′,6′-dioxa-1′-silacyclohexyl]tetracyclo[4.4.0.        1^(2,5).1^(7,10)]dodeca-3-ene, and the like.

Further, examples of specific monomers (c) having the hydrolysable silylgroup represented by general formula (5) include

-   -   5-triethoxysilylbicyclo[2.2.1]hept-2-ene,    -   5-methyldiethoxysilylbicyclo[2.2.1]hept-2-ene,    -   5-methyldimethoxysilylbicyclo[2.2.1]hept-2-ene,    -   5-dimethylchlorosilylbicyclo[2.2.1]hept-2-ene,    -   5-methyldiethoxysilylbicyclo[2.2.1]hept-2-ene,    -   5-methyldichlorosilylbicyclo[2.2.1]hept-2-ene,    -   5-tripropoxysilylbicyclo[2.2.1]hept-2-ene,    -   8-triethoxysilyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodeca3-ene,        and the like.

When the content of the repeating units (c) having a polar group such asa hydrolysable silyl group or an ester group is increased herein,adhesion or adhesiveness with other materials can be further improved,and the cyclic olefin addition copolymer of the present invention can beconverted to a crosslinked product by using a crosslinking agentdescribed later. However, on the other hand, an increase in the contentof the repeating units (c) having the polar group causes an increase inwater absorption properties and dielectric constant. Accordingly, theratio of the repeating units (c) represented by formula (3) in thecyclic olefin addition copolymer is 30 mol % or less, preferably from0.1 to 10 mol %, and more preferably from 1 to 5 mol %, in the wholerepeating units.

The repeating unit (c) having the hydrolysable silyl group representedby the above-mentioned general formula (5) is excellent in reactivitycompared to the case having the silyl group represented by theabove-mentioned general formula (4). Conversely, the repeating unit (c)having the hydrolysable silyl group represented by the above-mentionedgeneral formula (4) is more excellent in hydrolysis resistance, so thata solution of the cyclic olefin copolymer comes to have excellentstorage stability.

Further, addition polymerization is conducted using specific monomer (c)having an acryloyl group or a methacryloyl group, and such an acryloylgroup or methacryloyl group can also be utilized as a crosslinkingpoint. However, in this case, it is necessary to be designed so that theresulting copolymer is difficult to suffer oxidation by oxygen ordeterioration by heat even when hydrogenation thereof is not carriedout, such that specific monomer (a-1) is used as a monomer for givingthe repeating unit (a).

The cyclic olefin addition copolymer of the present invention canfurther contain a repeating unit (e) obtained by addition polymerizationof a “specific α-olefin compound”.

Specific examples of such specific α-olefin compounds include ethylene,propylene, 1-butene, 2-methylpropene(isobutene), trimethylvinylsilane,triethylvinylsilane, styrene, 4-methylstyrene, 2-methylstyrene,4-ethylstyrene and the like. They can be used either alone or as acombination of two or more of them.

The glass transition temperature of the cyclic olefin addition copolymerof the present invention can be controlled by introducing the “specificα-olefin compound”-derived repeating units (e) into the copolymer. Theratio of the repeating units (e) in the cyclic olefin addition copolymeris from 0 to 40 mol %, and preferably from 0 to 20 mol % (with theprovisothat the repeating unit (a)+(b)+(c)+(e)=100 mol %). When theratio of the repeating units (e) exceeds 40 mol %, the glass transitiontemperature of the cyclic olefin addition copolymer of-the presentinvention is lowered to deteriorate heat resistance.

The glass transition temperature of the cyclic olefin addition copolymerof the present invention is determined from the peak temperature oftemperature dispersion of tan δ measured by dynamic viscoelasticity(storage modulus: E′, loss modulus: E″, tan δ=E″/E′).

The glass transition temperature of the cyclic olefin addition copolymerof the present invention measured as described above is usually from 150to 450° C., and preferably from 200 to 400° C. When the glass transitiontemperature is lower than 150° C., the possibility increases that theproblem of thermal deformation or the like is encountered in the casethat a formed article containing the cyclic olefin addition copolymer ofthe present invention is processed or used. On the other hand, when itexceeds 450° C., the polymer becomes inflexible, and when the polymer isformed into a film or a sheet, the coefficient of linear expansiondecreases, but the film or the sheet become fragile and lose toughness.The glass transition temperature of the cyclic olefin addition copolymerin the present invention can be controlled by the selection of thesubstituent groups in the repeating units (b) and (c) and/or theintroduction of the repeating unit (e), for example, such as theintroduction of a straight chain alkyl substituent group. having 4 to 20carbon atoms into the repeating unit (c).

As for the molecular weight of the cyclic olefin addition copolymer inthe present invention, the polystyrene-converted number averagemolecular weight (Mn) measured by gel permeation chromatography usingo-dichlorobenzene as a solvent at 120° C. is from 30,000 to 500,000, andthe weight average molecular weight (Mw) is from 50,000 to 1,000,000.Preferably, it is desirable that the number average molecular weight isfrom 50,000 to 200,000 and the weight average molecular weight is from100,000 to 500,000.

When the number average molecular weight is less than 30,000 and theweight average molecular weight is less than 50,000, a film, a thinmembrane and a sheet formed are insufficient in breaking strength andelongation to become fragile in many cases. On the other hand, when thenumber average molecular weight exceeds 500,000 and the weight averagemolecular weight exceeds 1,000,000, the solution viscosity increases informing a cast film to cause poor storage stability of a solution,resulting in the difficulty of handling in some cases.

The coefficient of linear expansion of the cyclic olefin additioncopolymer of the present invention is 70 ppm/° C. or less, andpreferably 60 ppm/° C. or less. The coefficient of linear expansion inthe cyclic olefin addition copolymer of the present invention variesdepending on the selection of a substituent group on the repeating unit(b) or the repeating unit (c) and the ratio of the respective repeatingunits contained in the polymer. Exceeding 70 ppm/° C. is undesirablebecause the problem of deformation associated with changes in dimensionarises in the use environment with a large temperature variation in somecases.

The cyclic olefin addition copolymer of the present invention isproduced by indispensably requiring specific monomers (a-1) and/or (a-2)and specific monomer (b), and further addition copolymerizing specificmonomer (c) and/or the specific α-olefin compound used as needed, usinga nickel compound as a catalyst component. Production methods thereofare described below.

As the polymerization catalyst, there is used

-   -   (A) a multicomponent catalyst containing components represented        by the following 1) to 3):    -   1) a nickel compound,    -   2) a compound selected from a superacid, a Lewis acid and an        ionic boron compound, and    -   3) an organic aluminum compound, or    -   (B) a nickel complex having at least one nickel-carbon sigma        bond and a superacid anion as a counter anion. However, the        multicomponent catalyst of (A) is preferred because it requires        no complicated synthetic process.

(A): The multicomponent catalyst is composed of components containing1), 2) and 3) shown below.

1) Nickel Compound: at Least One Compound Selected from the Group ofCompounds Given Below

-   -   A compound selected from an organic carboxylate, organic        phosphite, organic phosphate, organic sulfonate, β-diketone        compound and the like of nickel. For example, nickel acetate,        nickel octanoate, nickel 2-ethylhexanoate, nickel naphthenate,        nickel oleate, nickel versatate, nickel dibutylphosphite, nickel        dibutylphosphate, nickel dioctylphosphate, a nickel salt of        dibutyl phosphate ester, nickel dodecylbenzene-sulfonate, nickel        p-toluenesulfonate, bis(acetylacetonato)-nickel, nickel        bis(ethylacetoacetate) and the like.    -   A compound obtained by modifying the above-mentioned organic        carboxylate of nickel with a superacid such as        hexafluoroantimonic acid, tetrafluoroboric acid,        trifluoro-acetic acid or hexafluoroacetone.    -   A diene or triene coordinate complex of nickel, for example, a        nickel complex such as    -   dichloro(1,5-cyclooctadiene)nickel,    -   [(η³-crotyl)(1,5-cyclooctadiene)nickel]hexafluorophosphate and        tetrafluoroborate thereof,    -   a tetrakis[3,5-bis(trifluoromethyl)]borate complex,    -   (1,5,9-cyclododecatriene)nickel,    -   bis[norbornadiene]nickel, or    -   bis(1,5-cyclooctadiene)nickel.

A complex in which a ligand having an atom such as P, N or O iscoordinated to nickel, for example, a nickel complex such as

-   -   bis(triphenylphosphine)nickel dichlorides    -   bis(triphenylphosphine)nickel dibromide,    -   bis[tri(2-methylphenyl)phosphine)nickel dichloride,    -   bis[tri(4-methylphenyl)phosphine)nickel dichloride,    -   bis[N-(3-t-butylsalicylidene)phenylaminato]nickel,    -   Ni[PhC(O)CH](Ph),    -   Ni(OC(C₆H₄)PPh)(H)(Pcy₃),    -   Ni[OC(O)(C₆H₄)P](H)(PPh₃),    -   a reaction product of bis(1,5-cyclooctadiene)nickel and        PhC(O)CH═PPh₃, or    -   [2,6-(I—Pr)₂C₆H₃N═CHC₆H₃(O)(Anth)](Ph)(PPh₃)Ni (wherein Anth:        9-anthracenyl, Ph: phenyl, Cy: cyclohexyl).

2) Compound Selected from Superacid, Lewis Acid and Ionic Boron Compound

The superacids include, for example, hexafluoroantimonic acid,hexafluorophosphoric acid, hexafluoroarsenic acid, trifluoroacetic acid,fluorosulfuric acid, trifluoro-methanesulfonic acid, tetrafluoroboricacid, tetrakis-(pentafluorophenyl)boric acid,tetrakis[3,5-bis(trifluoro-methyl)phenyl]boric acid, p-toluenesulfonicacid, penta-fluoropropionic acid and the like.

The Lewis acid compounds include, for example, boron compounds such as acomplex of boron trifluoride with an ether, an amine, a phenol or thelike, a complex of an aluminum trifluoride with an ether, an amine, aphenol or the like, tris(pentafluorophenyl)borane andtris[3,5-bis(trifluoro-methyl)phenyl]borane, aluminum compounds such asaluminum trichloride, aluminum tribromide, ethylaluminum dichloride,ethylaluminum sesquichloride, diethylaluminum fluoride andtri(pentafluorophenyl)aluminum, organic halogen compounds showing Lewisacidity such as hexafluoroacetone, hexa-chloroacetone, chloranil andhexafluoromethyl ethyl ketone, and other compounds showing Lewis aciditysuch as titanium trichloride and pentafluoroantimony, and the like.

The ionic boron compounds include, for example,

-   -   triphenylcarbenium tetrakis(pentafluorophenyl)borate,    -   triphenylcarbenium        tetrakis[3,5-bis(trifluoromethyl)-phenyl]borate,    -   triphenylcarbenium tetrakis(2,4,6-trifluorophenyl)-borate,    -   triphenylcarbenium tetraphenylborate,    -   tributylammonium tetrakis(pentafluorophenyl)borate,    -   N,N-dimethylanilinium tetrakis(pentafluorophenyl)-borate,    -   N,N-diethylanilinium tetrakis(pentafluorophenyl)-borate,    -   N,N-diphenylanilinium tetrakis(pentafluorophenyl)-borate and the        like.

3) Organic Aluminum Compound

There is suitably used, for example, an alkylalumoxane compound such asmethylalumoxane, ethylalumoxane or butyl-alumoxane, an alkylaluminumcompound and an alkylaluminum halide compound such as trimethylaluminum,triethylaluminum, triisobutylaluminum, diisobutylaluminum hydride,diethyl-aluminum chloride, diethylaluminum fluoride, ethylaluminumsesquichloride or ethylaluminum dichloride, a mixture of theabove-mentioned alkylalumoxane compound and the above-mentionedalkylaluminum compound, or the like. In particular, methylalumoxane oran organic aluminum component containing methylalumoxane is mostpreferred because of its slight decrease in polymerization activity whenpolar groupcontaining specific monomer (c) is used.

(B) The nickel complex having at least one nickel-carbon sigma bond anda superacid anion as a counter anion is represented by the followinggeneral formula (11):[L¹L²ML³]⁺[An]³¹   (11)

In formula (11), M represents a nickel atom. L¹, L² and L³represent aligand of M, a carbon atom of at least one ligand binds to a nickel atomby a a σ bond, and the others represent a compound selected from acycloalkadiene having 6 to 12 carbon atoms, norbornadiene, acycloalkatriene having 10 to 20 carbon atoms and an aromatic compoundhaving 6 to 20 carbon atoms. Further, [An]³¹ represents asuperacid-derived non-coordinate or weak coordinate counter anion. Thecounter anion [An]³¹ is preferably BF₄ ⁻, PF₆ ⁻, SbF₅SO₃F⁻, AlF₃SO₃CF₃⁻, AsF₆ ⁻, SbF₆ ⁻, AsF₆ ⁻, CF₃CO₂ ⁻, C₂F₅CO₂ ⁻, CH₃C₆H₄SO₃ ⁻, B[C₆F₅]₄ ⁻or B[3,5-(CF₃)₂C₆H₃]₄ ⁻.

Specific examples of the compounds represented by the above-mentionedgeneral formula (11) include but are not limited to

-   -   [η³-crotyl)Ni(cycloocta-1,5-diene)][B(3,5-(CF₃)₂C₆F₃)₄],    -   [η³-crotyl)Ni(cycloocta-1,5-diene)][PF₆],    -   [η³-allyl)Ni(cycloocta-1,5-diene)][B(C₆F₅)₄], and    -   [η³-crotyl)Ni(cycloocta-1,5-diene)][SbF₆], and the like.

These catalyst components are used in amounts within the followingranges.

The nickel compound is from 0.02 to 100 mmol atom per mol of monomer,the organic aluminum compound is from 1 to 5,000 mol per mol atom ofnickel, and the superacid is from 0.2 to 5.0 mol per mol atom of nickel.The Lewis acid is from 0 to 50 mol per mol atom of nickel.Alternatively, the nickel compound is from 0.02 to 100 mmol atom per molof monomer, the organic aluminum compound is from 1 to 5,000 mol pre molatom of nickel, and the ionic boron compound is from 0.2 to 5.0 mol permol atom of nickel.

When the nickel compound modified with the superacid is used as 1) thenickel compound in (A) the multicomponent catalyst of the presentinvention, the Lewis acid is not necessarily required. However, additionof the Lewis acid more improves polymerization activity. Further, whenthe chlorine-containing organic aluminum halide compound is used as theorganic aluminum component, addition of the Lewis acid is notnecessarily required.

Further, as the catalyst component of the present invention, addition ofone or two or more kinds of compounds selected from the superacid, theLewis acid and the ionic boron compound is necessary in (A) themulticomponent catalyst, and the non-coordinate or weak coordinatecounter ion derived from the superacid is necessary in (B) the singlecomponent catalyst. By using these catalysts, the repeating unit (d)derived from specific monomer (b) and formed by addition polymerizationat the 2,7-positions or the 3,11-positions is observed in the copolymerof the present invention, and the copolymer is improved in solubility intoluene, cyclohexane or a mixed solvent thereof at 25° C.

The cyclic olefin addition copolymer of the present invention can bepolymerized in one or two or more kinds of solvents selected from analicyclic hydrocarbon solvent such as cyclohexane, cyclopentane ormethylcyclopentane, an aliphatic hydrocarbon solvent such as hexane,heptane or octane, an aromatic hydrocarbon solvent such as toluene,benzene, xylene or mesitylene, a halogenated hydrocarbon solvent such aschloromethane, dichloromethane, 1,2-dichloroethane, 1,1-dichloroethane,tetrachloroethane, chloroform, carbon tetrachloride, chlorocyclopentane,chlorocyclohexane, chlorobenzene or dichlorobenzene, and the like, using(A) the above-mentioned multicomponent catalyst or (B) theabove-mentioned single component catalyst. Of these, toluene,cyclohexane, dichloromethane or a mixed solvent thereof is desirablyused from the viewpoints of general-purpose properties and the like.

As a polymerization method, a reaction vessel is charged withthesolvent, specificmonomers (a) and (b), andspecificmonomer (c) asneeded, further the specific α-olefin compound as needed, and amolecular weight modifier as needed, in a nitrogen or argon atmosphere,and the polymerization system is set to a temperature ranging from −20°C. to 100° C. Then, the above-mentioned catalyst component is added, andpolymerization is conducted at a temperature ranging from −20° C. to100° C. The weight ratio of solvents to monomers is from 1 to 20. Themolecular weight of the copolymer is adjusted by the amount of thepolymerization catalyst, the amount of the molecular weight modifieradded, the conversion rate to the polymer and the polymerizationtemperature. As the molecular weight modifier, there is used an α-olefinsuch as 1-hexene or 1-octene, an aromatic vinyl compound such asstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene,3,5-di-methylstyrene, 1-vinylnaphthalene or divinylbenzene, a cyclicunconjugated diene such as cyclooctadiene or cyclododecatriene,diphenyldihydrosilane, hydrogen or the like, and preferably used is thearomatic vinyl compound.

The termination of the polymerization is conducted by a compoundselected from water, an alcohol, an organic acid, carbon dioxide and thelike. Separation and removal of a catalyst residue may be appropriatelyconducted by known methods. For example, there is a method of addingwater/alcohol mixture of an organic acid selected from maleic acid,fumaric acid, oxalic acid, malic acid and the like to a polymer solutionto separate it from an aqueous layer. Further, the catalyst residue maybe removed by adsorption removal using an adsorbent such as diatomaceousearth, alumina or silica, or by filtration separation using a filter orthe like.

The polymer is obtained by pouring the polymer solution into an alcoholselected from methanol, ethanol, isopropanol and the like to coagulateit, and drying it under reduced pressure. In this step, unreactedmonomers remaining in the polymer solution are also removed.

The olefinic unsaturated bond-containing addition copolymer obtained bypolymerization using the monomer containing one or more kinds ofspecific monomers (a-2) described above is hydrogenated using thefollowing catalyst and conditions.

As the hydrogenation catalyst, there is suitably used one selected froma heterogeneous catalyst in which nickel, rhodium, palladium, platinumor the like is carried on a solid such as silica, diatomaceous earth,alumina or activated carbon, a homogeneous catalyst in which a compoundof titanium, nickel, palladium, cobalt or the like is combined with anorganic metal compound, a catalyst comprising a complex of ruthenium,osmium, rhodium, iridium or the like, and the like. As a solvent, thereis used an aromatic hydrocarbon such as toluene, xylene, ethylbenzene ortetralin, or an alicyclic hydrocarbon such as cyclohexane,methylpentane, methylcyclohexane or decalin, and an aliphatichydrocarbon such as hexane or heptane, an ether such as tetrahydrofuran,dimethoxyethane or butyl ether, or the like as needed. For theconditions, the hydrogen pressure and the temperature areappropriately-selected within the ranges of 0.5 to 15 MPa and 20 to 200°C., respectively.

The hydrogenated copolymer is treated in a manner similar to that of theafter treatment of the polymerization. A catalyst residue is removedusing an organic acid or an absorbent, and coagulation is conductedusing steam or an alcohol, followed by separation and drying to recoverthe polymer.

The cyclic olefin addition copolymer of the present invention can alsobe blended with a hydrogenated product of a known cyclic olefinring-opened (co)polymer or an addition copolymer of a cyclic olefin withethylene to form a polymer blend composition. The formation of thepolymer blend composition can control the glass transition temperatureof the cyclic olefin addition copolymer of the present invention withoutimpairing the toughness thereof, and makes possible the adjustment andmodification of optical characteristics of a formed article such as afilm or a sheet by heat treatment, injection molding, compressionmolding and the like. Further, the cyclic olefin addition copolymer ofthe present invention can be blended with a petroleum resin having analicyclic hydrocarbon structure, a hydrogenated styrenic resin or thelike, thereby being able to control softening temperature, birefringenceor the like while retaining transparency.

In such a composition, for the compounding ratio of the cyclic olefinaddition copolymer of the present invention to the above-mentionedhydrogenated ring-opened (co) polymer, the ratio of the cyclic olefinaddition copolymer of the present invention in the cyclic olefinaddition copolymer in the composition is from 10 to 90% by weight,preferably from 20 to 80% by weight, and more preferably from 30 to 70%by weight.

To the cyclic olefin addition copolymer of the present invention, therecan be added, for example, a phenolic or hydroquinone antioxidant suchas

-   -   2,6-di-t-butyl-4-methylphenol    -   4,4′-thiobis-(6-t-butyl-3-methylphenol)    -   1,1′-bis(4-hydroxyphenyl)cyclohexane,    -   2,2′-methylenebis(4-ethyl-6-t-butylphenol),    -   2,5-di-t-butylhydroquinone, or    -   pentaerythrityltetrakis[3-(3,5-di-t-butyl-4-hydroxy-phenyl)propionate].

Further, it is possible to blend a phosphorus antioxidant such as

-   -   tris(4-methoxy-3,5-diphenyl)phosphite,    -   tris(nonylphenyl)phosphite,    -   tris(2,4-di-t-butylphenyl)phosphite    -   bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite,        or    -   bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite,    -   thereby being able to improve oxidation stability.

Of these compounds, a compound having a decomposition temperature (a 5%decrease in weight) of 250° C. or higher is preferred.

When these antioxidants are added, they are added within the range of0.05 to 5.0 parts by weight per 100 parts by weight of the cyclic olefinaddition copolymer.

The cyclic olefin addition copolymer of the present invention can befurther converted to a crosslinkable composition and a crosslinkedproduct using method shown below.

1) In crosslinking by radicals, the following compositions andcrosslinking methods are employed. In that case, the crosslinked productcan be formed more easily in the cyclic olefin addition copolymer usingthe repeating unit (c) having a methacryloyl group or an acryloyl groupin a side-chain substituent group.

a) A composition in which the copolymer is blended with a peroxide or anazo compound, and a method of crosslinking the composition by radicalsgenerated using heat or active light.

b) A composition with a peroxide and a reducing metal compound, and amethod of crosslinking the composition by radicals generated by redoxreaction.

2) In crosslinking the copolymer using a hydrolytic silylgroup-containing unit as the repeating unit (c) by hydrolysis andcondensation reaction, the following compositions are used.

a) A composition with an oxide, an alkoxide, a phenoxide, aβ-diketonate, an alkylate, a halide, an organic acid salt or the like ofa metal such as tin, aluminum, zinc, titanium or antimony.

b) A composition with a compound acting as an acid by heating, such asan aromatic sulfonium salt, an aromatic ammonium salt, an aromaticpyridinium salt, an aromatic phosphonium salt, an aromatic iodoniumsalt, a hydrazinium salt or a ferrocenium salt, which has a counteranion selected from BF₄, PF₄, AsF₆, SbF₆, B(C₆F₅)₄ and the like.

c) A composition with a compound acting as an acid by heating in thepresence of water or steam, such as a trialkylphosphite, atriarylphosphite, dialkylphosphite, monoalkylphosphite, a hypophosphite,an ester of an organic carboxylic acid with a secondary or tertiaryalcohol, a hemiacetal-ester of an organic carboxylic acid, atrialkylsilyl ester of an organic carboxylic acid, a monocyclic orpolycyclic cycloalkyl ester of an alkylsulfonic acid or a monocyclic orpolycyclic cycloalkyl ester of an alkylarylsulfonic acid.

d) A composition with a photoacid generator which forms a Bronsted acidor a Lewis acid by irradiation of light rays such as g-rays, h-rays,i-rays, ultraviolet rays, far ultraviolet rays, X-rays or electron rays,for example, an onium salt such as a diazonium salt, an ammonium salt, aiodonium salt, a sulfonium salt, a phosphonium salt, an arsenium salt oran oxonium salt, a halogenated organic compound such as ahalogen-containing oxadiazole compound, a halogen-containing triazinecompound, a halogen-containing acetophenone compound or ahalogen-containing benzophenone compound, a quinone diazide compound, anα,α-bis(sulfonyl)diazomethane compound, anα-carbonyl-α-sulfonyl-diazomethane compound, a sulfonyl compound, anorganic acid ester compound, an organic acid amide compound or anorganic acid imide compound.

3) In the copolymer using an eater group-containing unit as therepeating unit (c), a composition with a polyhydric alcohol having 2 to4 hydroxyl groups per molecule and the metal compound described in theabove 2), a) as the catalyst is crosslinked by ester exchange reaction,thereby being able to form the crosslinked product.

A compound selected from these peroxide, azo compound, metal compound of2), a) to d), acid-generating ester compound, thermal acid generator andpolyhydric compound and the like is blended with the cyclic olefinaddition copolymer of the present invention to form the crosslinkablecomposition, thereby being able to obtain the crosslinked product of thecyclic olefin addition copolymer under a relatively mild temperaturecondition of 10 to 280° C. In particular, the use of the compound actingas an acid by heating in the presence of water or steam described in 2),c) is preferred because not only the pot life of the composition isprolonged to give excellent storage stability, but also thecharacteristics of the crosslinked product obtained by heat treating thecomposition in the presence of water or steam, such as dimensionalstability and solvent and chemical resistance, become excellent.

The crosslinked product of the present invention retains the excellentoptical characteristics of the cyclic olefin addition copolymer, andfurther, the heat resistance is more enhanced, because it iscrosslinked, to show a lower coefficient of linear expansion than theuncrosslinked copolymer, giving excellent breaking strength, breakingelongation, solvent and chemical resistance, and liquid crystalresistance.

The compound used for the above-mentioned crosslinking applications isblended within the range of 0.0001 to 5.0 parts by weight per 100 partsby weight of the cyclic olefin addition copolymer of the presentinvention.

In the crosslinkable composition of the present invention, there canalso be further incorporated at least one compound selected from analkoxide or allyloxide compound of a metal selected from silicon,titanium, aluminum and zirconium, and a condensate of the metal alkoxidehaving a condensation degree of 3 to 30. It becomes easy to obtain acrosslinked structure effective for improving dimensional stability orsolvent and chemical resistance when the crosslinked product is formed,by incorporating such a compound. Specific examples thereof includetetramethoxysilane, tetraethoxysilane, tetra-isopropoxysilane,methyltrimethoxysilane, methyltri-ethoxysilane, dimethyldimethoxysilane,dimethyldiethoxy-silane, cyclohexyltrimethoxysilane,cyclohexyltriethoxy-silane, dicyclohexyldimethoxysilane,cyclopentyltrimethoxy-silane, bicyclo[2.2.1]hept-2-yltrimethoxysilane,2-bicyclo-[2.2.1]heptene-5-yltrimethoxysilane, aluminum trimethoxide,aluminum triethoxide, titanium tetraethoxide, zirconium tetraethoxide, acondensate thereof having a condensation degree of 3 to 30, and thelike. Further, a composition with a silane compound having a radicallypolymerizable substituent group such as a methacryloyl group or anacryloyl group and a radical generator can be formed, and crosslinked bylight or heat to obtain the crosslinked product.

In the composition with the above-mentioned alkoxide or allyloxidecompound of a metal selected from silicon, titanium, aluminum andzirconium, or with the condensate thereof having a condensation degreeof 3 to 30, it is preferably incorporated with in the range of 5 to 60parts by weight per 100 parts by weight of the cyclic olefin additioncopolymer of the present invention.

Further, in addition to the above-mentioned alkoxide or allyloxidecompound of a metal selected from silicon, titanium, aluminum andzirconium; or the condensate thereof having a condensation degree of 3to 30, particles or colloidal particles of a metal oxide such as silica,alumina, zirconia, titania or the like, which have an average particlesize of 100 nm or less, may be blended to form a composition, andfurther a crosslinked product.

For the blending amount of the above-mentioned metal oxide (the blendingamount converted to the solid content in the colloidal particles), it isblended in an amount of 1 to 40 parts by weight per 100 parts by weightof the cyclic olefin addition copolymer of the present invention. Whenthe blending amount thereof is less than 1 part by weight, the effect ofimprovement by the metal oxide is insufficient in the hardness, elasticmodulus, and coefficient of linear expansion of the crosslinked productobtained by crosslinking. On the other hand, when it exceeds 40 byweight, the crosslinked product obtained by crosslinking becomes brittlein some cases.

The cyclic olefin addition copolymer (composition) of the presentinvention can be formed into a thin membrane, a film or a sheet by thesolution cast method of dissolving the copolymer (composition) in asolvent selected from a hydrocarbon solvent, a halogenated hydrocarbonsolvent and a mixed solvent thereof, applying or flow casting thesolution onto a steel belt, a carrier film or the like, followed by adrying step to obtain a formed article. Further, the copolymer(composition) can also be swelled in the solvent, and then, formed andprocessed into a thin membrane, a film or a sheet while evaporating thesolvent in an extruder. Furthermore, the copolymer can also be blendedwith another thermoplastic resin to form a polymer blend composition,and formed into a thin membrane, a film or a sheet by a melt extrusionmethod using a melt extruder or the like.

Further, the cyclic olefin addition copolymer and hydrolysable silylgroup- or ester group-containing cyclic olefin addition copolymer(composition) of the present invention are excellent in adhesioness orstickiness with other materials, so that they are also useful as athin-film coating material or an adhesive.

The film or sheet containing the cyclic olefin addition copolymer of thepresent invention, the composition thereof and the crosslinked productthereof can satisfy heat resistance, washing resistance, transparency,adhesioness/stickiness and dimensional stability required for substratematerials in the steps of exposure, development, etching and the like inTFT (thin-film transistor) formation on substrates, and further, liquidcrystal resistance and the like in liquid crystal injection, so that itis useful as an optical material used as a substrate for a flat display,such as a liquid crystal display element or an electroluminescencedisplay element.

Further, the cyclic olefin addition copolymer of the present invention,the composition thereof, the crosslinked product thereof and thematerial containing the composition of the present invention haveexcellent optical transparency, low birefringence, heat resistance,adhesioness/stickiness, and low moisture absorption, so that they areuseful as an optical material used for an optical waveguide, apolarizing film, a surface protective film, a light diffusion film, aphase difference film, a transparent conductive film, an antireflectionfilm, an OHP film, an optical disk, an optical fiber, a lens and thelike. Furthermore, they are also useful as electronic parts, a coatingagent, an adhesives, further a medical container and a container.

EXAMPLES

The present invention will be illustrated in greater detail withreference to the following examples, but the invention should not beconstrued as being limited thereby.

Parts and percentages are based on weight, unless otherwise specified.

Further, the molecular weight, the change in hue by a thermal stabilitytest, the total light transmittance, the glass transition temperature,the coefficient of linear expansion, the adhesioness/stickiness, thedegree of swelling in toluene, the tensile strength, the elongation, thesolution viscosity and a solubility test were measured by the followingmethods:

(1) ¹H-NMR:

¹H-NMR was measured in a mixed solvent of benzene-d₆ ando-dichlorobenzene (volume ratio: 60/40), with heating as needed, at aresonant frequency of 270 MHz.

(2) Weight Average Molecular Weight and Number Average Molecular Weight:

The molecular weights were measured at 120° C. using a 150 C type gelpermeation chromatography (GPC) system manufactured by Waters and an Htype column manufactured by Tosoh Corporation, and usingO-dichlorobenzene as a solvent. The resulting molecular weight is astandard polystyrene-converted value.

(3) Change in Hue by Thermal Stability Test:

A film was heat treated in the air at 240° C. for 1 hour, and the yellowindex (YI value) was measured with transmitted light according to JISK7105 for the film before and after the treatment. A change in hue wasevaluated by a change thereof (ΔYI).

(4) Total Light Transmittance:

A film having a thickness of 150 μm was formed, and the total lighttransmittance was measured in accordance with ASTM-D1003.

(5) Peak Temperature of Tan δ (Glass Transition Temperature):

The glass transition temperature of a polymer was measured by the peaktemperature of Tan δ (the ratio of loss modulus E″ to storage modulusE′, E″/E′=Tan δ) of dynamic viscoelasticity. The measurement of dynamicviscoelasticity was made using Leovibron DDV-01FP (manufactured byOrientic Co. Ltd.), and the glass transition temperature was determinedby the peak temperature of temperature variance of Tan δ obtained at ameasurement frequency of 10 Hz, at a rate of temperature increase of 4°C./minute, at a single waveform vibration mode and at a vibrationamplitude of 2.5 μm.

(6) Coefficient of Linear Expansion:

Using TMA (Thermal Mechanical Analysis)/SS6100 (manufactured by SeikoInstrument Co., Ltd.), a sample having a film thickness of 100 μm, awidth of 3 mm and a length of 10 cm or more was fixed thereto at a chuckdistance of 10 mm, and once heated from room temperature to about 200°C. to remove residual strain. Then, the temperature of the sample waselevated from room temperature at 3° C./min., and the coefficient oflinear expansion was determined from the elongation of the chuckdistance.

(7) Adhesioness/Stickiness:

Aluminum was deposited on a test piece of 10 cm×10 cm, and the depositedfilm was cut with a cutter so as to form 10×10 squares of 1 mm×1 mm. Apeeling test using a cellophane tape was conducted, and the number ofpeeled blocks of 25 blocks was measured.

(8) Degree of Swelling in Toluene:

A film about 50 to 250 μm in thickness and 2 cm×2 cm in length and widthwas immersed in toluene at 25° C. for 3 hours, and the weight of thefilm before and after the immersion was measured. The degree of swellingwas calculated by the following equation:Degree of swelling in toluene (%)=(weight of the film after immersion intoluene/weight of the film before immersion in toluene)×100

(9) Breaking Strength and Breaking Elongation:

A test piece was measured at a tensile rate of 3 mm/min. in accordancewith JIS K7113.

(10) Solution Viscosity of Copolymer and Copolymer Composition:

The solution viscosity of a copolymer and a copolymer composition wasmeasured at 25° C. using an RE80L rotational viscometer manufactured byTOKI Sangyo Co., Ltd. and 3°×R14 as a rotor.

(11) Solubility Test of Copolymer:

Five grams of a copolymer and 50 ml of a solvent were mixed in a 100-mlglass vial, and stirred at 50° C. for 2 hours. Then, the solution wascooled to 25° C. spending one hour, and the appearance of the polymersolution in the vial was observed.

-   -   ◯ . . . Dissolved (insoluble: less than 0.1%)    -   Δ . . . Partially dissolved (insoluble: 0.1 to 95%)    -   X . . . Not dissolved (insoluble: 95% or more)    -   ● . . . Dissolved only under heating at 120° C. or higher        (insoluble: less than 0.1%)    -   ▴ . . . Partially dissolved only under heating at 120° C. or        higher (insoluble: 0.1 to 95%)

(12) Analysis of Unreacted Monomer:

A part of a polymerization reaction solution was collected, and tetralinwas added as a standard material. The solution was coagulated withisopropyl alcohol. Using a GC-14B gas chromatography system manufacturedby Shimadzu Corporation, and using a TC-1 capillary column (filmthickness: 1.0 μm, internal diameter: 0.25 mm, length: 60 m, columntemperature: 200° C.) manufactured by GL Sciences Inc. as a column, theamounts of unreacted monomers remaining in a supernatant after thecoagulation were determined, and the contents of the respective monomercomponents contained in the copolymer were calculated. The monomers usedas raw materials were subjected to the gas chromatography analysis underthe same analysis conditions.

SYNTHESIS EXAMPLES

As endo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene, a commercially availableone was purified by distillation under reduced pressure to use. Theendo/exo ratio analyzed by gas chromatography was 99/1 or more.

endo-Tricyclo[4.3.0.1^(2,5))deca-3-ene was synthesized with reference tomethods described in U.S. Pat. No. 4,139,569 and Makromol. Chem., Vol.95, 179 (1966), and purified by distillation under reduced pressureusing a distilling apparatus having a theoretical plate number of 40.The resulting product having a purity of 99% or more and an endo/exoratio of 90/10 or 96/4 was used.

exo-Tricyclo[4.3.0.1^(2,5)]deca-3,7-diene was synthesized with referenceto methods described in J. Am. Chem. Soc., 69, 2553 (1947) and Synthesis105 (1975), and purified by distillation under reduced pressure. Theresulting product having a purity of 99% or-more and an endo/exo ratioof 4/96 was used.

exo-Tricyclo[4.3.0.1^(2,5)]deca-3-ene was synthesized with reference tomethods described in J. Am. Chem. Soc., 69, 2553 (1947), J. Am. Chem.Soc., Vol. 82, 2351 (1960) and Synthesis 105 (1975), and purified bydistillation under reduced pressure. The resulting product having apurity of 99% or more and an endo/exo ratio of 10/90 was used.

endo-Tricyclo[4.4.0.1^(2,5)]undeca-3,7-diene was obtained by reactingdicyclopentadiene with 1,3-cyclohexadiene by the Diels-Alder reactionusing a known technique, and performing purification under reducedpressure. The resulting product having a purity of 99% or more and anendo/exo ratio of 85/15 was used.

endo-Tricyclo[4.4.0.1^(2,5)]trideca-3,11-diene was obtained by reactingdicyclopentadiene with 1,3-cyclo-octadiene by the Diels-Alder reactionusing a known technique, and performing purification under reducedpressure. The resulting product having a purity of 99% or more and anendo/exo ratio of 80/120 was used.

Example 1

A 2-liter stainless steel reaction vessel was charged with 47 g (500mmol) of bicyclo[2.2.1]hept-2-ene, 66 g (500 mmol) ofendo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene, 0.42 g (5 mmol) of 1-hexene,and 480 g of toluene and 85 g of cyclohexane as solvents under nitrogen.

A hexane solution of nickel octanoate was reacted withhexafluoroantimonic acid at −10° C. at a molar ratio of 1:1, and aprecipitate of nickel bis(hexafluoroantimonate) [Ni(SbF₆)₂] formed as aby-product was removed by filtration. The resulting product was dilutedwith toluene. A reaction vessel was charged with 0.40 mmol (as a nickelatom) of the resulting hexafluoroantimonic acid-modified product ofnickel octanoate, 1.2 mmol of boron trifluoride ethyl etherate, 8.0 mmolof methylalumoxane, 0.4 mmol of 1,5-cyclooctadiene and 8.0 mmol ofmethyltriethoxysilane in the order of methyltriethoxysilane,1,5-cyclooctadiene, methylalumoxane, boron trifluoride ethyl etherateand the hexafluoroantimonic acid-modified product of nickel octanoate,and polymerization was initiated. The polymerization was conducted at30° C. for 3 hours, and methanol was added to terminate thepolymerization. The conversion rate of the monomers to the copolymer was73%.

To the copolymer solution, 480 g of cyclohexane was added to dilute it,and 660 ml of water and 48 mmol of lactic acid were added thereto,followed by sufficient stirring and mixing. Then, the copolymer solutionand an aqueous phase were separated from each other by still standing.The aqueous phase containing a reaction product of the catalystcomponent was removed, and the copolymer solution was poured into 4 L ofisopropyl alcohol to coagulate the copolymer, thereby removing unreactedmonomers and a catalyst residue. The coagulated copolymer was dried toobtain 75 g of copolymer A. By ¹H-NMR measurement of the copolymer andgas chromatography analysis of the unreacted monomers, the content ofstructural units derived from endo-tricyclo[4.3.0.1^(2,5)]deca-3,7-dienein copolymer A was 37 mol %. (The ratio of the structure derived fromtricyclo-[4.3.0.1^(2,5)]deca-3,7-diene in copolymer A was determinedfrom the ratio of absorption caused by a cyclopentene ring olefinstructure derived from tricyclo[4.3.0.1^(2,5)]deca-3,7-diene at 5.5 to6.2 ppm to that caused by all protons of a norbornene ring at 0.7 to 3.3ppm, and further, the ratio of the structure derived fromendo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene in copolymer A was determinedfrom the amounts of unreacted endo- andexo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene charged and determined by gaschromatography analysis. The same method was also used in the followingexamples and comparative examples.)

The polystyrene-converted number average molecular weight (Mn) ofcopolymer A was 82,000, the weight average molecular weight (Mw) was151,000, and Mw/Mn was 1.8.

Thirty grams of this copolymer A was dissolved in a mixed solvent of 285g of cyclohexane and 285 g of toluene, and hydrogenation was conductedin a 2-liter pressure vessel using 2.2 mg of a ruthenium catalystrepresented by RuHCL(CO)[PPh₃]₃ at a hydrogen pressure of 8 MPa at 180°C. for 4 hours. After hydrogen was purged, 50 g of diatomaceous earth(Radiolite #800 manufactured by Showa Chemical Industry Co., Ltd.) wasadded to the copolymer solution, followed by stirring at 60° C. for 2hours. Then, diatomaceous earth was separated by filtration. Thehydrogenated copolymer solution after the separation by filtration waswashed with an aqueous solution of lactic, acid to remove a catalystresidue, and coagulated with isopropyl alcohol to obtain 25 g ofhydrogenated copolymer AH. The rate of hydrogenation of copolymer AHdetermined from ¹H-NMR measurement was 99%. A ¹H-NMR spectrum ofcopolymer AH is shown in FIG. 1. Further, the results of the solubilitytest of copolymer AH are shown in Table 1.

Then, 10 g of hydrogenated copolymer AH was dissolved in 35.5 g ofcyclohexane, andpentaerythrityltetrakis-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]was added as an antioxidant in an amount of 1.0 part based on 100 partsof the copolymer. A film was prepared from this copolymer solution by acast method, and dried at 150° C. for 2 hours and further at 200° C. for1 hour under vacuum to prepare film AH-1 having a thickness of 150 μm.As the evaluation results shown in Table 2, the film was littlediscolored at high temperatures, and excellent in breakingstrength/breaking elongation.

Comparative Example 1

Ten grams of unhydrogenated copolymer A was dissolved in 35.5 g ofcyclohexane, andpentaerythrityltetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]was added as an antioxidant in an amount of 1.0 part based on 100 partsof the copolymer. A film was prepared from this copolymer solution by acast method, and dried at 150° C. for 2 hours and further at 200° C. for1 hour under vacuum to prepare film A-1 having a thickness of 150 μm.From the evaluation results shown in Table 2, the film was clearlyinferior in heat deterioration resistance and breaking strength/breakingelongation, compared to AH-1.

Example 2

Polymerization was conducted in the same manner as with Example 1 withthe exception that 625 mmol of bicyclo-[2.2.1]hept-2-ene, 587 mmol ofendo-tricyclo[4.3.0.1^(2,5)]-deca-3,7-diene and 37 mmol of5-triethoxysilylbicyclo-[2.2.1]hept-2-ene were used as monomers, therebyobtaining copolymer B at a conversion rate of 62%. The ratio ofstructural units derived from endo-tricyclo[4.3.0.1^(2,5)]deca-3,7-dienein copolymer B was 37 mol %. Further, the ratio of structural unitsderived from 5-triethoxysilylbicyclo[2.2.1]hept-2-ene, which wasdetermined from a ¹H-NMR spectrum, was 3.0 mol % (calculated from theratio of CH₂ absorption of an Si—O—CH₂— group at 3.7 to 4.1 ppm toabsorption of all other protons). The polystyrene-converted numberaverage molecular weight of copolymer B was 60,000, the weight averagemolecular weight was 121,000, and Mw/Mn was 2.0.

Then, using the above-mentioned copolymer B in place of copolymer A andthe same solvent and catalyst as with Example 1, hydrogenation wasconducted at a hydrogen pressure of 8 MPa at 120° C. for 4 hours. Acopolymer solution was treated by the same technique as with Example 1to obtain hydrogenated copolymer BH. The rate of hydrogenation ofcopolymer BH determined from ¹H-NMR measurement was 99%. A ¹H-NMRspectrum of copolymer BH is shown in FIG. 2, and further, the results ofthe solubility test are shown in Table 1.

Then, 10 g of hydrogenated copolymer BH was dissolved in 35.5 g ofcyclohexane.Pentaerythrityltetrakis[3-(3,5di-t-butyl-4-hydroxyphenyl)propionate] wasadded as an antioxidant in an amount of 1.0 part based on 100 parts ofthe copolymer, and tributyl phosphite was added as a crosslinkingcatalyst in an amount of 0.5 part based on 100 parts of the copolymer.The solution viscosity (25° C.) of this copolymer composition was 2,200(cp). The solution viscosity (25° C.) after storage of this copolymersolution in a hermetically sealed glass container for 1 week was 2,400(cp) A film was prepared from this copolymer solution by a cast method,and dried at 150° C. for 2 hours and further at 200° C. for 1 hour undervacuum to prepare uncrosslinked film BH-1 having a thickness of 150 μm.Further, film BH-1 was heat treated under steam of 150° C. for 4 hours,and then, dried at 200° C. for 1 hour under vacuum to obtain crosslinkedfilm BH-2. As apparent from the evaluation results of BH-1 and BH-2shown in Table 2, the transparency of the film was kept, even after heattreatment, and the film was excellent in braking strength/breakingelongation. In addition, by using5-triethoxysilylbicyclo-[2.2.1]hept-2-ene and further conductingtreatment-with steam, crosslinking reaction effectively proceeds,braking strength/elongation were further improved, and the film becameinsoluble in toluene to provide the film excellent in chemicalresistance/solvent resistance.

Comparative Example 2

Ten grams of copolymer B obtained in Example 2 was dissolved in 35.5 gof cyclohexane, andpentaerythrityl-tetrakis[3(3,5-di-t-butyl-4-hydroxyphenyl)propionate]was added as an antioxidant in an amount of 1.0 part based on 100 partsof the copolymer, and tributyl phosphite was added as a crosslinkingcatalyst in an amount of 0.5 part based on 100 parts of the copolymer.This copolymer solution was cast, and a film formed was dried at 150° C.for 2 hours and further at 200° C. for 1 hour under vacuum to prepareunhydrogenated/uncrosslinked film B-1 having a thickness of 150 μm.Further, film B-1 was heat treated under steam of 150° C. for 4 hours,and then, dried at 200° C. for 1 hour under vacuum to obtainunhydrogenated/crosslinked film B-2.

The evaluation results of films B-1 and B-2 are shown in Table 2. In theunhydrogenated copolymer, the film was remarkably discolored to yellowafter heat treatment, regardless of whether the film had beencrosslinked or uncrosslinked, resulting in [the film having low heatdeterioration resistance.

Example 3

Polymerization was conducted in the same manner as with Example 1 withthe exception that 625 mmol of bicyclo-[2.2.1]hept-2-ene, 587 mmol ofendo-tricyclo[4.3.0.1^(2,5)]-deca-3,7-diene and 37 mmol of5-[1′,4′,4′-trimethyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo[2.2.1]hept-2-enewere used as monomers, thereby obtaining copolymer C. The conversionrate to the copolymer was 60%. The ratio of structural units derivedfrom endo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene in copolymer C was 36mol %. Further, the ratio of structural units derived from5-[1′,4′,4′-trimethyl-2′,6′-dioxa-1′-sila-cyclohexyl]bicyclo[2.2.1]hept-2-ene,which was determined from a 1H-NMR spectrum, was 3.0 mol % (calculatedfrom the ratio of CH₂ absorption of an Si—O—CH₂— group at 3.4 to 4.0 ppmto absorption of all other protons). The polystyrene-converted numberaverage molecular weight of copolymer C was 116,000, the weight averagemolecular weight was 278,000, and Mw/Mn was 2.4.

Then, using the above-mentioned copolymer C, hydrogenation and aftertreatment were conducted by the same technique as with Example 2 toobtain hydrogenated copolymer CH. The rate of hydrogenation of copolymerCH determined from ¹H-NMR measurement was 99%. A ¹H-NMR spectrum ofcopolymer CH is shown in FIG. 3, and the results of the solubility testare shown in Table 1.

Then, 10 g of hydrogenated copolymer CH was dissolved in 35.5 g ofcyclohexane.Pentaerythrityltetrakis[3-(3,5di-t-butyl-4-hydroxyphenyl)propionate] wasadded as an antioxidant in an amount of 1.0 part based on 100 parts ofthe polymer, and tributyl phosphite was added as a crosslinking catalystin an amount of 0.5 part based on 100 parts of the polymer. The solutionviscosity (25° C.) of this copolymer composition was 3,100 (cp). Thesolution viscosity (25° C.) after storage of this copolymer solution ina hermetically sealed glass container for 1 week was 3,150 (cp). A filmwas prepared from this copolymer solution by a cast method, and dried at150° C. for 2 hours and further at 200° C. for 1-hour under vacuum toprepare uncrosslinked film CH-1 having a thickness of 150 μm. Further,film CH-1 was heat treated under steam of 150° C. for 4 hours, and then,dried at 200° C. for 1 hour under vacuum to obtain crosslinked filmCH-2. As apparent from the evaluation results of shown in Table 2, thefilm obtained from copolymer CH was excellent in thermal stability.Further, by conducting treatment with steam, crosslinking reactioneffectively proceeds, braking strength/elongation were further improved,and the film became insoluble in toluene to provide the film excellentin chemical resistance/solvent resistance. In addition, by using5-[1′,4′,4′-trimethyl-2′,6′dioxa-1′silacyclohexyl]bicyclo[2.2.1]hept-2-eneas a crosslinking group-containing monomer, the solution viscosity ofthe copolymer composition was scarcely changed even after 1 week, andthe solution was more excellent in storage stability.

Comparative Example 3

Ten grams of copolymer C obtained in Example 3 was dissolved in 35.5 gof cyclohexane, andpentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]was added as an antioxidant in an amount of 1.0 part based on 100 partsof the copolymer, and tributyl phosphite was added as a crosslinkingcatalyst in an amount of 0.5 part based on 100 parts of the copolymer.This copolymer solution was cast, and a film formed was dried at 150° C.for 2 hours and further at 200° C. for 1 hour under vacuum to prepareunhydrogenated/uncrosslinked film C-1 having a thickness of 150 μm.Further, film C-1 was heat treated under steam of 150° C. for 4 hours,and then, dried at 200° C. for 1 hour under vacuum to obtainunhydrogenated/crosslinked film C-2.

The evaluation results of films C-1 and C-2 are shown in Table 2. In theunhydrogenated copolymer, the film was remarkably discolored to yellowafter heat treatment, regardless of whether the film had beencrosslinked or uncrosslinked, resulting in the film having low heatdeterioration resistance.

Example 4

Polymerization was conducted in the same manner as with Example 3 withthe exception that 78 g of toluene, 168 g of cyclohexane and 164 g ofmethylene chloride were used as solvents, thereby obtaining copolymer Dat a conversion rate of 93%. The ratio of structural units derived fromendo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene in copolymer D was 40 mol %,and the ratio of structural units derived from5-[1′,4′,4′-trimethyl-2′,6′-dioxa-1′-silacyclohexyl]-bicyclo[2.2.1]hept2-enewas 3.0 mol %.

The polystyrene-converted number average molecular weight of copolymer Dwas 112,000, the weight average molecular weight was 224,000, and Mw/Mnwas 2.0.

The above-mentioned copolymer D was hydrogenated by the same techniqueas with Example 2 to obtain hydrogenated copolymer DH. The rate ofhydrogenation determined from a ¹H-NMR spectrum of polymer DH was 99%.The ¹H-NMR spectrum of copolymer DH is shown in FIG. 3, and the resultsof the solubility test are shown in Table 1.

Then, using copolymer DH, uncrosslinked film DH-1 and crosslinked filmDH-2 were prepared by the same technique as with Example 2. Theevaluation results of film DH-2 are shown in Table 2.

Example 5

Polymerization was conducted in the same manner as with Example 4 withthe exception that 587 mmol of endo-tri-cyclo[4.3.0.1^(2,5)]deca-3-ene(endo/exo=96/4) was used as a monomer in place ofendo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene, thereby obtaining copolymerE at a conversion rate of 90%. The ratio of structural units derivedfrom5-[1′,4′,4′-tri-methyl-2′,6′-dioxa-1′-silacyclohexyl]bicyclo-[2.2.1]hept-2-enein copolymer E was 2.8 mol %. Further, the ratio of structural unitsderived from endo-tricyclo[4.3.0.1^(2,5)]deca3-ene in copolymer E was 39mol %. The polystyreneconverted number average molecular weight ofcopolymer E was 108,000, the weight average molecular weight was211,000, and Mw/Mn was 2.0.

A ¹H-NMR spectrum of copolymer E is shown in FIG. 5, and the results ofthe solubility test of copolymer E are shown in Table 1.

Then, 10 g of copolymer E was dissolved in 35.5 g of cyclohexane, andpentaerythrityltetrakis[3-(3,5-di-tbutyl4-hydroxyphenyl)propionate] wasadded as an antioxidant in an amount of 1.0 part based on 100 parts ofthe copolymer, and tributyl phosphite was added as a crosslinkingcatalyst in an amount of 0.5 part based on 100 parts of the copolymer.This copolymer solution was cast, and a film formed was dried at 150° C.for 2 hours and further at 200° C. for 1 hour under vacuum to prepareuncrosslinked film E-1 having a thickness of 150 μm. Further, this filmwas heat treated under steam of 150° C. for 4 hours, and then, dried at200° C. for 1 hour under vacuum to obtain crosslinked film E-2. Theevaluation results of film E-2 are shown. By usingendo-tricyclo[4.3.0.1^(2,5)]deca-3-ene which is a monomer having nounsaturated bond on its side chain, the film having a smaller change inhue by heat and excellent in stability compared to hydrogenatedcopolymers (AH to DH) prepared in Examples 1 to 4 was obtained withoutgoing through the hydrogenation process.

Example 6

Operations were conducted in the same manner as with Example 2 with theexception that 37 mmol of5-(methyl-diethoxysilyl)bicyclo[2.2.1]hept-2-ene was used as a monomerin place of 5-triethoxysilylbicyclo[2.2.1]hept2-ene, thereby obtainingcopolymer F at a conversion rate of 52%.

The ratio of structural units derived fromendo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene in copolymer F was 34 mol %.Further, the ratio of structural units derived from5-(methyldiethoxysilyl)bicyclo[2.2.1]hept-2-ene, which was determinedfrom a ¹H-NMR spectrum, was 2.5 mol % (calculated from the ratio of CH₂absorption of an Si—O—CH₂— group at 3.6 to 4.0 ppm to absorption of allother protons). The polystyrene-converted number average molecularweight of copolymer F was 72,000, the weight average molecular weightwas 165,000, and Mw/Mn was 2.3.

Using the above-mentioned copolymer F, hydrogenation was conducted bythe same technique as with Example 2 to obtain hydrogenated copolymerFH. The rate of hydrogenation determined from a ¹H-NMR spectrum ofcopolymer FH was 99%. The ¹H-NMR spectrum of copolymer FH is shown inFIG. 6, and the results of the solubility test of copolymer FH are shownin Table 1.

Then, uncrosslinked film FH-1 was prepared from copolymer FH by the sametechnique as with Example 2. Further, film FH-1 was subjected tocrosslinking treatment by the same technique as with Example. 2 toprepare crosslinked film FH-2. The evaluation results of film FH-2 areshown in Table 2.

Example 7

Using 78 g of toluene, 168 g of cyclohexane and 164 g of methylenechloride as solvents, and 1020 mmol of bicyclo-[2.2.1]hept-2-ene, 190mmol of endo-tricyclo[4.3.0.1^(2,5)]-deca3,7-diene and 40 mmol of5-triethoxysilylbicyclo[2.2.1]hept2-ene as monomers, copolymer G wasobtained at a conversion rate of 92% by the same technique as withExample 4. The ratio of structural units derived fromendo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene in copolymer G was 15 mol %,and the ratio of structural units derived from5-triethoxysilylbicyclo[2.2.1]hept-2-ene was 3.0 mol %. Thepolystyrene-converted number average molecular. weight of copolymer Gwas 72,000, the weight average molecular weight was 143,000, and Mw/Mnwas 2.0.

The above-mentioned copolymer G was hydrogenated by the same techniqueas with Example 2 to obtain hydrogenated copolymer GH. The rate ofhydrogenation determined from a ¹H-NMR spectrum of copolymer GH was 99%.The ¹H-NMR spectrum of copolymer GH is shown in FIG. 7, and the resultsof the solubility test of copolymer GH are shown in Table 1.

Uncrosslinked film GH-1 and crosslinked film GH-2 were prepared fromcopolymer GH by the same technique as with Example 2. The evaluationresults of film GH-2 are shown in Table 2.

Example 8

Copolymer H was obtained at a conversion rate of 77% in the same manneras with Example 1 with the exception that 500 mmol ofbicyclo[2.2.1]hept-2-ene, 400 mmol ofendotri-cyclo[4.3.0.1^(2,5)]deca3-ene having an endo/exo ratio of 90/10and 100 mmol of 5-hexylbicyclo[2.2.1]hept2-ene were used as monomers.The ratio of structural units derived fromendo-tri-cyclo[4.3.0.1^(2,5)]deca-3-ene in copolymer H was 31 mol %.Further, the ratio of structural units derived from5-hexylbicyclo[2.2.1]hept-2-ene, which was determined from a ¹H-NMRspectrum, was 8 mol % (calculated from the ratio of absorption of aterminal methyl group of a hexyl group at 0.9 to 1.1 ppm to absorptionof all other protons).

The polystyrene-converted number average molecular weight of copolymer Hwas 137,000, the weight average molecular weight was 261,000, and Mw/Mnwas 1.9.

The ¹H-NMR spectrum of copolymer H is shown in FIG. 8, and the resultsof the solubility test of copolymer H are shown in Table 1.

Subsequently, film H-1 having a thickness of about 150 μm was preparedfrom copolymer H in the same manner as with Example 1. The evaluationresults of film H-1 are shown in Table 2.

Example 9

Copolymer I was obtained at a conversion rate of 75% in the same manneras with Example 1 with the exception that 750 mmol ofbicyclo[2.2.1]hept-2-ene, 450 mmol ofendotri-cyclo[4.3.0.1^(2,5)]deca3-ene (endo/exo ratio: 96/4) and 50 mmolof8-methyl-8-carboxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-dodeca3-eneas monomers. The ratio of structural units derived fromendo-tricyclo[4.3.0.1^(2,5)]deca-3-ene in copolymer I was 29 mol %.Further, the ratio of structural units derived from8-methyl-8-carboxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]-dodeca-3-ene,which was determined from a ¹H-NMR spectrum, was 4 mol % (calculatedfrom the ratio of absorption at 3.3 to 3.7 ppm to absorption of allother protons). The polystyrene-converted number average molecularweight of copolymer I was 89,000, the weight average molecular weightwas 177,000, and Mw/Mn was 2.0. The ¹H-NMR spectrum of copolymer I isshown in FIG. 9, and the results of the solubility test of copolymer Iare shown in Table 1.

Subsequently, film I-1 having a thickness of about 150 μm was preparedfrom copolymer I in the same manner as with Example 1. The evaluationresults of film I-1 are shown in Table 2.

Example 10

Operations were conducted in the same manner as with Example 4 with theexception that 625 mmol of bicyclo-[2.2.1]hept-2-ene, 587 mmol ofendo-tricyclo[4.4.0.1^(2,5)]-undeca-3,7-diene (endo/exo=85/15) and 37mmol of 5-tri-ethoxysilylbicyclo[2.2.1]hept-2-ene were-used as monomers,and 78 g of toluene, 168 g of cyclohexane and 164 g of methylenechloride were used as solvents, thereby obtaining copolymer J at aconversion rate of 85%. The ratio of structural units derived fromendo-tricyclo[4.4.0.1^(2,5)]undeca-3,7-diene in copolymer J was 33 mol%, and the ratio of structural units derived from5-triethoxysilylbicyclo[2.2.1]hept-2-ene was 3.0 mol %. Thepolystyrene-converted number average molecular weight of copolymer J was102,000, the weight average molecular weight was 197,000, and Mw/Mn was1.9.

Using the above-mentioned copolymer J, hydrogenation was conducted bythe same technique as with Example 2 to obtain hydrogenated copolymerJH. The rate of hydrogenation of copolymer JH determined from a ¹H-NMRspectrum was 99%. The ¹H-NMR spectrum of copolymer JH is shown in FIG.10, and the results of the solubility test of polymer JH are shown inTable 1. Uncrosslinked film JH-1 and crosslinked film JH-2 were preparedfrom polymer JH by the same technique as with Example 2. The evaluationresults of film JH-2 are shown in Table-2.

Example 11

Polymerization was conducted by the same technique as with Example 10with the exception that 587 mmol oftricyclo-[6.4.0.1^(2.5)]trideca-3,11-diene (endo/exo=80/20) was used asa monomer in place of endo-tricyclo[4.4.0.1^(2,5) ]undeca-3,7-diene toobtain copolymer K at a conversion rate of 65%.

The ratio of structural units derived fromendo-tricyclo[6.4.0.1^(2,5)]trideca-3,11-diene in copolymer K was 30 mol%, and the ratio of structural units derived from5-triethoxysilylbicyclo[2.2.1]hept-2-ene was 2.5 mol %. Thepolystyrene-converted number average molecular weight of copolymer K was83, 000, the weight average molecular weight was 167,000, and Mw/Mn was2.0.

Using the above-mentioned copolymer K, hydrogenation was conducted bythe same technique as with Example 2 to obtain hydrogenated copolymerKH. The rate of hydrogenation of copolymer KH determined from a ¹H-NMRspectrum was 99%. The ¹H-NMR spectrum of copolymer KH is shown in FIG.11. Further, the results of the solubility test of copolymer KH areshown in Table 1.

Uncrosslinked film KH-1 and crosslinked film KH-2 were prepared fromcopolymer KH by the same technique as with Example 10. The evaluationresults of crosslinked film KH-2 are shown in Table 2.

Example 12

Operations were conducted in the same manner as with Example 4 with theexception that 700 mmol of bicyclo-[2.2.1]hept-2-ene, 570 mmol ofendo-tricyclo[4.3.0.1^(2,5)]-deca-3-ene (endo/exo=96/4), 30 mmol of5-triethoxysilyl-bicyclo[2.2.1]hept-2-ene and 5 mmol of 1-hexene wereused as monomers, and 400 g of cyclohexane and 100 g of methylenechloride were used as solvents, thereby obtaining copolymer L at aconversion rate of 92%. The ratio of structural units derived from5-triethoxysilylbicyclo[2.2.1]hept-2-ene in copolymer L was 2.1 mol %,and the ratio of structural units derived fromendo-tricyclo[4.3.0.1^(2,5)]deca-3-ene was 35 mol %. Thepolystyrene-converted number average molecular weight of copolymer L was89,000, the weight average molecular weight was 187,000, and Mw/Mn was2.1. The 1H-NMR of copolymer L is shown in FIG. 12, and the results ofthe solubility test are shown in Table 1.

Then, using the above-mentioned copolymer L, uncrosslinked film L-1 andcrosslinked film L-2 were prepared by the same operations as withExample 5. From the evaluation results of crosslinked film L-2 are shownin Table 2, the film was apparently excellent in breakingstrength/breaking elongation, solvent resistance and heat deteriorationresistance.

Comparative Example 4

A 2-liter reaction vessel was charged with 625 mmol ofbicyclo[2.2.1]hept-2-ene, 587 mmol ofendo-tricyclo-[4.3.0.1^(2,5)]deca-3,7-diene, 37 mmol of5-[1′,4′,4′-trimethyl2′,6′dioxa-1′-silacyclohexyl]bicyclo-[2.2.1]hept-2-eneand 5 mmol of 1-hexene as monomers, and 350 g of chlorobenzene and 285 gof cyclohexane as solvents under nitrogen.

The reaction vessel was charged with 0.40 mmol (converted to a palladiumatom) of an η³-allylpalladium chloride dimer and 0.8 mmol of silverhexafluoroantimonate as catalyst components in this order, andpolymerization was conducted at 30° C. for 3 hours. A white polymerstarted to precipitate for 10 minutes after the initiation ofpolymerization, and solidified in slurry form after 1 hour. Thepolymerization was terminated with methanol, and the precipitatedpolymer was separated by filtration to obtain copolymer M. Theconversion rate of the monomers was 88%. The results of the solubilitytest of copolymer M are shown in Table 1. This copolymer M obtained bypolymerization using the palladium compound as the catalyst wasinsoluble in toluene, cyclohexane and a mixed solvent of both.

Then, copolymer M was hydrogenated in a slurry state just like Example2. However, hydrogenation reaction did not proceed.

Comparative Example 5

Polymerization was conducted in the same manner as with ComparativeExample 4 with the exception that 950 mmol ofendo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene, 50 mmol of5-[1′,4′,4′trimethyl-2′,6′dioxa-1′-silacyclohexyl]bicyclo-[2.2.1]hept-2-eneand 5 mmol of 1-hexene were used as monomers, 0.4 mmol oftetrakis(acetonitrile)palladiumbis(tetra-fluoroborate)[Pd(CH₃CN)₄](BF₄)₂ was used as a catalystcomponent in place of the η³-allylpalladium chloride dimer and silverhexafluoroantimonate, and 500 g of nitromethane as a solvent. As aresult, copolymer N precipitated similarly to Comparative Example 4. Theconversion rate of the monomers to the copolymer was 90%.

The results of the solubility test of copolymer N are shown in Table 1.Similarly to copolymer M shown in Comparative Example 4, copolymer N wasinsoluble in all solvents tested, resulting in failure to prepare afilm.

Comparative Example 6

Using 625 mmol of bicyclo[2.2.1]hept-2-ene, 587 mmol ofexo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene (endo/exo=4/96) and 37 mmolof.5[1′,4′,4′trimethyl2′,6′dioxa-1′-silacyclohexyl]-bicyclo[2.2.1]hept-2-eneas monomers, polymerization was conducted under the same conditions aswith Example 3 to obtain copolymer O at a conversion rate of 75%. Theratio of structural units derived fromexo-tricyclo[4.3.0.1^(2,5)]deca3,7-diene in copolymer O was 24 mol %.Further, the ratio of structural units derived from5-[1′,4′,4′-trimethyl2′,6′-dioxa-1′silacyclo-hexyl]bicyclo[2.2.1]hept2-enewas 3.0 mol %. The polystyrene-converted number average molecular weightof copolymer O was 82,000, the weight average molecular weight was166,000, and Mw/Mn was 2.0.

Then, hydrogenation of copolymer O was conducted by the same operationsas with Example 3 to obtain hydrogenated copolymer OH. The rate ofhydrogenation determined from a ¹H-NMR spectrum of copolymer, OH was99%. The results of the solubility test of copolymer O are shown inTable 1.

Then, using copolymer OH, uncrosslinked film OH-1 and crosslinked filmOH-2 were prepared by the same technique as with Example 3. From theevaluation results of film OH-2 shown in Table 2, this copolymer inwhich exo-tricyclo-[4.3.0.1^(2,5)]deca-3,7-diene having a highproportion of the exo form was used was largely inferior in physicalcharacteristics such as breaking strength, compared to one of Example 3.

Comparative Example 7

Polymerization was conducted by the same operations as with Example 12with the exception that 1080 mmol ofendo-tricyclo[4.3.0.1^(2,5)]deca-3-ene (endo/exo=96/4) and 40 mmol of5-triethoxysilylbicyclo[2.2.1]hept-2-ene were used as monomers withoutadding bicyclo[2.2.1]hept-2-ene. However, copolymer P precipitatedduring polymerization. The conversion rate of the monomers to thecopolymer was 50%.

The resulting copolymer P was insoluble in all of toluene, cyclohexaneand a mixed solvent thereof, so that it was unable to prepare a film.The results of the solubility test of copolymer P are shown in Table 1.

Comparative Example 8

Polymerization was conducted by the same operations as with Example 12with the exception that 560 mmol ofexo-tricyclo[(4.3.0.1^(2,5)]deca-3-ene (endo/exo=10/90) was used as amonomer in place of endo-tricyclo[4.3.0.1^(2,5)]deca-3-ene, therebyobtaining copolymer Q at a conversion rate of 97%. The ratio ofstructural units derived from exo-tricyclo-[4.3.0.1^(2,5)]deca-3-ene incopolymer Q was 42 mol %, and the ratio of structural units derived from5-triethoxysilylbicyclo-[2.2.1]hept-2-ene was 3.1 mol %. Further, thepolystyrene-converted number average molecular weight of copolymer Q was119,000, the weight average molecular weight was 250,000, and Mw/Mn was2.1. Uncrosslinked film Q-1 and crosslinked film Q-2 were prepared fromthe resulting copolymer Q. From the evaluation results shown in Table 2,it was apparently inferior in breaking strength/breaking elongation,compared to copolymer L of Example 12 usingendo-tricyclo[4.3.0.1^(2,5)]-deca-3-ene.

Comparative Example 9

Operations were conducted in the same manner as with Example 1 with theexception that 1,000 mmol of bicyclo-[2.2.1]hept-2-ene and 2 mmol ofstyrene were used as monomers, thereby obtaining copolymer R at aconversion rate of 98%. The polystyrene-converted number averagemolecular weight of copolymer R was 195,000, the weight averagemolecular weight was 492,000, and Mw/Mn was 2.5. Further, the results ofthe solubility test of copolymer R are shown in Table 1.

Then, 10 g of copolymer R was dissolved in 35.5 g of cyclohexane, theantioxidant was added in the same manner as with Example 1, anduncrosslinked film R-1 having a thickness of 150 μm was prepared bycasting. The evaluation results of film R-1 are shown in Table 1. Theresulting film was weak in breaking strength and brittle, so that it waseasily broken by even a small external force.

Comparative Example 10

Operations were conducted in the same manner as with Example 4 with theexception that 970 mmol of bicyclo-[2.2.1]hept-2-ene and 30 mmol of5[1′,4′,4′trimethyl2′,6′-dioxa-1′-silacyclohexyl]bicyclo[2.2.1]hept-2-enewere used as monomers, thereby obtaining copolymer S at a conversionrate of 98%. The ratio of structural units derived from5[1′,4′,4′-trimethyl2′,6′dioxa-1′-silacyclohexyl]bicyclo-[2.2.1]hept-2-enein copolymer S was 2.8 mol %. The polystyreneconverted number averagemolecular weight of copolymer S was 116,000, the weight averagemolecular weight was 278,000, and Mw/Mn was 2.4. Further, the results ofthe solubility test of copolymer S are shown in Table 1.

Then, 10 g of copolymer S was dissolved in 35.5 g of cyclohexane, theantioxidant and the crosslinking catalyst were added in the same manneras with Example 2, and uncrosslinked film S-1 having a thickness of 150μm and crosslinking film S-2 were prepared by a cast method. Theresulting film was weak in breaking strength and brittle, so that it waseasily broken by even a small external force. The evaluation results offilms S-1 and S-2 are shown in Table 2.

Comparative Example 11

Operations were conducted in the same manner as with Example 2 with theexception that 1,200 mmol of bicyclo-[2.2.1]hept-2-ene, 50 mmol oftricyclo[4.3.0.1^(2,5)]-deca-3,7-diene having an endo-form ratio of 99%or more and 30 mmol of5[1′,4′,4′trimethyl2′,6′dioxa-1′-silacyclohexyl]-bicyclo[2.2.1]hept-2-enewere used as monomers, thereby obtaining copolymer T at a conversionrate of 98%. The ratio of structural units derived fromendo-tricyclo-[4.3.0.1^(2,5)]deca-3,7-diene in copolymer T was 4 mol %,and the ratio of structural units derived from5-[1′,4′,4′tri-methyl]-2′,6′-dioxa-1′silacyclohexyl]bicyclo[2.2.1]hept2-enewas 2.8 mol %. The polystyreneconverted number average molecular weightof copolymer T was 120,000, the weight average molecular weight was243,000, and Mw/Mn was 2.0.

Using the above-mentioned copolymer T, hydrogenation was conducted bythe same technique as with Example 2 to obtain hydrogenated copolymerTH. The rate of hydrogenation determined from a ¹H-NMR spectrum ofcopolymer TH was 99%. The results of the solubility test of copolymer THare shown in Table 1. Subsequently, uncrosslinked film TH-1 was preparedby the same technique as with Example 2. Further, film TH-1 wascrosslinked by the same technique as with Example 2 to preparecrosslinked film TH-2. The evaluation results of film TH-2 are shown inTable 2. The resulting film was brittle and broken by even a smallexternal force, and showed low breaking strength. Like this, when theratio of structural units derived fromendo-tricyclo[4.3.0.1^(2,5)]deca-3,7-diene is less than 10 mol %, thefilm having weak braking strength is obtained.

Comparative Example 12.

Copolymer U was obtained at a conversion rate of 65% in the same manneras with. Example 2 with the exception that 625 mmol ofbicyclo[2.2.1]hept-2-ene, 587 mmol ofendo-tri-cyclo[4.3.0.1^(2,5)]deca-3,7-diene and 38 mmol of5-[1′,4′,4′tri-methyl-2′,6′-dioxa-1′silacyclohexyl]bicyclo[2.2.1]hept2-enewere used as monomers, and 300 mmol of 1,3-butadiene was used in placeof 1-hexene. The ratio of structural units derived fromendo-tricyclo[4.3.0.1^(2,5)]deca-3-ene in copolymer U was 37 mol %, andthe ratio of structural units derived from5-[1′,4′,4′trimethyl-2′,6′-dioxa1′silacyclohexyl]bicyclo-[2.2.1]hept-2-enewas 2.5 mol %. The polystyreneconverted number average molecular weightof copolymer U was 8,500, the weight average molecular weight was16,800, and Mw/Mn was 2.0.

The resulting copolymer U was hydrogenated by the same technique as withExample 2 to obtain copolymer UH at a rate of hydrogenation of 99%. Theresults of the solubility test of copolymer UH are shown in Table 1.

Uncrosslinked film UH-1 and crosslinked film UH-2 were prepared fromcopolymer UH by the same technique as with Example 2. The evaluationresults of film UH-2 are shown in Table 2. This film was very brittleand easily broken by even a small external force, so that it was unableto measure many physical properties. Like this, when the number averagemolecular weight of the copolymer was less than 30,000, particularly10,000 or less, only the very brittle film was obtained.

Comparative Example 13

Using the same solvent and catalyst as with Example 3, 30 g of copolymerC was hydrogenated at a hydrogen pressure of 5 MPa at 100 ° C. for 2hours. As a result, hydrogenated copolymer VH was obtained in which therate of hydrogenation determined from a ¹H-NMR spectrum was 70%. Theresults of the solubility test of copolymer VH are shown in Table 1.

Then, using 10 g of copolymer VH, uncrosslinked film VH-1 having athickness of 150 μm and crosslinked film VH-2 were obtained by the sametechnique as with Example 2. As apparent from the evaluation results offilm VH-2 shown in Table 2, the copolymer low in the rate ofhydrogenation resulted in the film largely inferior in heatdeterioration resistance, compared to CH-2. TABLE 1 Solubility inSolvent Copolymer Toluene Cyclohexane Chlorobenzene ChlorocyclohexaneDecalin Example 1 AH ◯ ◯ ◯ ◯ ◯ Example 2 BH ◯ ◯ ◯ ◯ ◯ Example 3 CH ◯ ◯ ◯◯ ◯ Example 4 DH ◯ ◯ ◯ ◯ ◯ Example 5 E ◯ ◯ ◯ ◯ ◯ Example 6 FH ◯ ◯ ◯ ◯ ◯Example 7 GH ◯ ◯ ◯ ◯ ◯ Example 8 H ◯ ◯ ◯ ◯ ◯ Example 9 I ◯ ◯ ◯ ◯ ◯Example 10 JH ◯ ◯ ◯ ◯ ◯ Example 11 KH ◯ ◯ ◯ ◯ ◯ Example 12 L ◯ ◯ ◯ ◯ ◯Comparative A ◯ ◯ ◯ ◯ ◯ Example 1 Comparative B ◯ ◯ ◯ ◯ ◯ Example 2Comparative C ◯ ◯ ◯ ◯ ◯ Example 3 Comparative M X X X X X Example 4Comparative N X X X X X Example 5 Comparative OH ◯ ◯ ◯ ◯ ◯ Example 6Comparative P X X X ▴ ▴ Example 7 Comparative Q ◯ ◯ ◯ ◯ ◯ Example 8Comparative R ◯ ◯ ◯ ◯ ◯ Example 9 Comparative S ◯ X ◯ ◯ ◯ Example 10Comparative TH ◯ ◯ ◯ ◯ ◯ Example 11 Comparative UH ◯ ◯ ◯ ◯ ◯ Example 12Comparative VH ◯ ◯ ◯ ◯ ◯ Example 13

TABLE 2 Coefficient Degree of Breaking Glass of Adhesion SwellingStrength/ Total Light Transition Linear (Number in BreakingTransmittance Temperature Expansion of Peeled Toluene Elongation Film(%) (° C.) ΔYI (ppm/° C.) Blocks) (%) (Mpa/%) Example 1 AH-1 90 375 1.856 10 Dissolved 39.2/3.8 Example 2 BH-1 91 365 1.7 54 0 Dissolved40.6/4.0 BH-2 91 370 1.9 51 0 180 51.9/6.4 Example 3 CH-1 91 380 2.1 560 Dissolved 29.6/3.8 CH-2 90 380 2.0 54 0 180 31.8/4.5 Example 4 DH-2 90370 2.3 55 0 190 32.5/4.4 Example 5 E-2 90 375 0.6 54 0 175 31.1/4.5Example 6 FH-2 90 380 2.2 54 1 190 36.1/3.9 Example 7 GH-2 90 360 1.5 530 195 28.7/3.6 Example 8 H-1 90 350 0.5 60 5 Dissolved 40.3/4.0 Example9 I-1 91 390 0.9 55 1 Dissolved 37.2/3.4 Example 10 JH-2 90 365 2.0 53 0190 45.7/8.7 Example 11 KH-2 90 355 2.1 50 0 180 34.1/3.7 Example 12 L-291 375 0.6 50 1 180 49.5/6.3 Comparative A-1 90 370 16 59 10 Dissolved16.2/1.3 Example 1 Comparative B-2 90 360 17 57 0 180 16.8/1.8 Example 2Comparative C-1 90 375 14 59 1 Dissolved 17.0/2.0 Example 3 C-2 48 38018 58 15 270 19.0/2.5 Comparative M (Impossible to cast*) Example 4Comparative N (Impossible to cast*) Example 5 Comparative OH-1 91 3902.0 49 0 250 14.7/1.6 Example 6 OH-2 91 390 2.0 48 0 220 16.7/1.9Comparative P (Impossible to cast*) Example 7 Comparative Q-2 91 390 1.049 0 190 18.5/2.0 Example 8 Comparative R-1 90 350 0.8 53 10 Dissolved20.9/1.9 Example 9 Comparative S-1 91 360 0.5 54 1 Dissolved 18.4/3.7Example 10 S-2 90 365 0.6 50 0 210 19.8/3.2 Comparative TH-2 90 365 1.552 1 200 22.0/3.1 Example 11 Comparative UH-2 90 Unmeasurable 2.0Unmeasurable 2 400 Unmeasurable Example 12 Comparative VH-2 88 375 12 571 210 25.5/3.1 Example 13*)It was impossible to cast the polymer, because it was insoluble intoluene, cyclohexane, a mixed solvent thereof and other practicalsolvents.

INDUSTRIAL APPLICABILITY

According to the present invention, the material excellent in opticaltransparency and heat resistance, excellent in toughness and low in thecoefficient of linear expansion, and therefore suitable for a film, asheet and a thin membrane for optical material applications is obtainedby the copolymer soluble in any one of toluene, cyclohexane and a mixedsolvent thereof at 25° C., which is obtained by addition polymerizationof the monomer containing a side chain substituent group having a ringstructure and the cyclic olefin in which the ratio of the endo-form is80% or more, using the specific nickel catalyst, and furtherhydrogenation as needed.

1. A cyclic olefin addition copolymer characterized in that the cyclic olefin addition copolymer contains at least one repeating unit (a) selected from repeating units represented by the following formulas (1-1) to (1-4) and a repeating-unit (b) represented by the following general formula (2), and is obtained by addition polymerization of a tricycloolefin compound which forms the repeating unit (a) after addition polymerization and the ratio of the endo-form (stereoisomer) of which is 80% or more, or further hydrogenating the resulting copolymer when an olefinic unsaturated bond exists therein, the cyclic olefin addition copolymer being homogeneously soluble in any one of toluene, cyclohexane and a mixed solvent thereof at 25° C., and having a polystyrene-converted number average molecular weight ranging from 30,000 to 500,000:

In formulas (1-1) to (1-4), R¹ to R²⁰ each independently represent a substituent group selected from a hydrogen atom, a halogen atom and a hydrocarbon or halogenated hydrocarbon group having 1 to 20 carbon atoms;

In formula (2), A¹ to A⁴ each independently represent a hydrogen atom, a halogen atom or a hydrocarbon or halogenated hydrocarbon group having 1 to 20 carbon atoms, and m is 0 or
 1. 2. The cyclic olefin addition copolymer according to claim 1, wherein the ratio of the endo-form (stereoisomer) in the tricycloolefin compound which forms the repeating unit (a) after addition polymerization is 90% mol or more.
 3. The cyclic olefin addition copolymer according to claim 1 or 2, wherein the ratio (molar ratio) of the repeating units (a) to the repeating units (b), (a)/(b), is from 80/20 to 10/90.
 4. The cyclic olefin addition copolymer according to any one of claims 1 to 3, which indispensably contains the repeating unit represented by the above-mentioned general formula (1-1) as the repeating unit (a).
 5. The cyclic olefin addition copolymer according to any one of claims 1 to 4, which indispensably contains the repeating unit represent ed by the above-mentioned general formula (2) wherein m=0 as the repeating unit (b).
 6. The cyclic olefin addition copolymer according to any one of claims 1 to 5, which contains a repeating unit (c) represented by the following general formula (3) in an amount of 0.1 to 30 mol % in the whole repeating units:

In formula (3), B¹ to B⁴ each independently represent a hydrogen atom, a halogen atom, a hydrocarbon or halogenated hydrocarbon group having 1 to 20 carbon atoms, a hydrolysable silyl group or a polar group represented by —(CH₂)_(k)X, and at least one of B¹ to B⁴ is a hydrolysable silyl group or a substituent group selected from polar groups represented by —(CH₂)_(k)X, wherein X is —C(O)OR²¹ or —OC(O)R²², R²¹and R²² are a substituent group selected from hydrocarbon or halogenated hydrocarbon groups having 1 to 20 carbon atoms, and k is an integer of 0 to
 3. Further, B¹ to B⁴ may be a ring structure such as a hydrocarbon or heterocyclic ring formed from B¹ and B³ or B² and B⁴, or an alkylidenyl group formed from B¹ and B² or B³ and B⁴. p represents an integer of 0 to
 2. 7. The cyclic olefin addition copolymer according to claim 6, which indispensably contains a repeating unit (c) having at least one hydrolysable silyl group.
 8. The cyclic olefin addition copolymer according to claim 7, which contains a silyl group represented by the following general formula (4) or general formula (5) as the hydrolysable silyl group:

In formula (4) and formula (5), R²³, R²⁴ and R²⁵ each independently represent a hydrogen atom or a substituent group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group and an aryl group, R²⁶, R²⁷ and R²⁸ each independently are a hydrogen atom or a substituent group selected from an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group, an aryl group, an alkoxyl group, an allyloxy group and a halogen atom, at least one of R²⁶, R²⁷ and R²⁸ is a substituent group selected from an alkoxyl group, an allyloxy group and a halogen atom, and n represents an integer of 0 to
 5. Further, Y represents a hydrocarbon residue of an aliphatic diol having 2 to 20 carbon atoms, an aliphatic diol or an aromatic diol.
 9. The cyclic olefin addition copolymer according to any one of claims 2 to 8, which contains a repeating unit (d) represented by the following-general formula (6):

In formula (6), A¹ to A⁴ and m are the same as defined for general formula (2).
 10. The cyclic olefin addition copolymer according to any one of claims 1 to 9, which has a glass transition temperature of 150 to 450° C.
 11. The cyclic olefin addition copolymer according to any one of claims 1 to 10, which has a coefficient of linear expansion of 70 ppm/° C. or less.
 12. A method for producing the cyclic olefin addition copolymer according to any one of claims 1 to 11, which is characterized in that a compound indicated by the following (A) or (B) is used as a polymerization catalyst: (A): A multicomponent catalyst containing components represented by the following 1) to 3): 1) A nickel compound, 2) A compound selected from a superacid, a Lewis acid and an ionic boron compound, and 3) An organic aluminum compound; (B) A nickel compound having at least one nickel-carbon sigma bond and a superacid anion as a counter anion.
 13. The method according claim 12, wherein the compound indicated by the above (A) as the polymerization catalyst, and methylalumoxane is used as a main component of the organic aluminum compound.
 14. A crosslinkable composition containing the cyclic olefin addition copolymer according to any one of claims 1 to 11 and at least one selected from a radical generator, an acid generator, a catalyst for ester exchange and a polyhydric alcohol.
 15. A crosslinked product obtained by forming the crosslinkable composition according to claim 14, and then, crosslinking the resulting formed article.
 16. An optical material containing the cyclic olefin addition copolymer according to any one of claims 1 to 11, the crosslinkable composition according to claim 14 or the crosslinked product according to claim
 15. 17. The optical material according to claim 16, which is in thin membrane, sheet or film form.
 18. The optical material according to claim 17, which is formed by a cast method. 